There are exceptions, of course, books I want so badly that I'll pay any amount of money to get them in my hands as soon as I can. These painful precipitants of expensive longing include books released in the United Kingdom before they appear in the United States (if, that is, they are published here at all). International shipping charges are extortionate, but I simply had to have Kazuo Ishiguro's latest novel the instant it came out in England. Other Amazon UK sprees have included the intelligent and vaguely Joan Aikenesque romances of Victoria Clayton, who when she was a teenager in the early 1970s published two delightful children's books (The Winter of Enchantment and The House Called Hadlows) under her maiden name Victoria Walker, and new novels by Diana Wynne Jones and Eva Ibbotson, books which at once enchant and torment me by seeming always to be released months sooner on the other side of the Atlantic. It is both sinister and convenient, the way that as an American customer you don't even have to re-enter any of your information (passwords, payment details, shipping addresses) on the British site.

Online shopping finds its psychic home in the hours after midnight when you can't sleep and you're bouncing off the walls just desperate for something good to read. Not that you're not surrounded by books already, but it's like looking in the fridge when you're hungry late at night: you could perfectly well eat that strawberry yogurt (it's not even past its sell-by date!) or the grilled chicken breast left over from dinner but somehow all you can think about is the local sushi place which closed hours ago. Of course there is a certain masochistic fulfillment to sitting there at the computer and placing an Amazon order with money you don't have, it's a lot like smoking too many cigarettes or using a blunt pair of scissors to cut your bangs too short in the bathroom mirror, they are all activities whose allure swells with every hour past midnight.

So one night in early January (this is 2006 I'm talking about) I put a bunch of stuff in the shopping cart and paid for it all and then more or less forgot about it until the box showed up a week later. I retrieved it from the hallway, tucked it under my arm and let myself into the apartment. I dropped my bag on the floor, then slit the tape along the seam of the box with my keys and dealt with the annoying inflated plastic packing thingy (what is the name for those useless pouches?). Inside I found new translations of two major canonical Russian novels (presumably ordered in the grip of an attraction not nearly strong enough to survive the presence of their actual Oprah-sanctioned heft) and a just-released hardcover novel that seemed in contrast to be vibrating audibly with desirability.

After making the sound Homer Simpson makes when he sees a donut, I picked the book up in my left hand and started reading the first lines of the opening as I stumbled in the direction of the bathroom. I awkwardly used my right hand to unbutton my jeans and pull down my underpants to pee; I didn't want to put the book down even for a second.

Now, if you don't really care about books, you might want to skip the next part. What you've already read is mainly in aid of setting the scene of my compulsions, and so as long as you're obsessed with something (Nigella Lawson's chocolate-cake recipes, for instance, or baseball or knitting or whatever—the details are immaterial) you can probably identify with me. But the book I had in my hand that night in January was genuinely drool-worthy in a way that's difficult for me to get across to the non-avid-novel-reader. It was Michael Chabon's The Yiddish Policemen's Union , one of the most anticipated releases of 2006; I knew it was going to be magically good and it completely lived up to my expectations, I turned off my phone and lay down on my stomach on the bed and read like a maniac all the way through to the end. The only thing I wanted after that was to turn the clock back six hours and have the whole thing to read all over again.

A confession: for years I turned up my nose at Michael Chabon without having read him. Something about the eagerness, the love even, with which his fans spoke of his writing just annoyed me. (Mostly—I am perfectly willing to admit this, I am not a good person—out of irritation and envy at not being a critically acclaimed and also best-selling novelist myself.) I did not see the movie adaptation of Wonder Boys , nor did I read the book; I did not care to read the irritatingly titled Mysteries of Pittsburgh and when I checked The Amazing Adventures of Kavalier & Clay out of the library I found the dust-jacket distinctly off-putting and returned it without having even cracked it open when it was recalled for another patron's use. And though I once accidentally claimed to have read Chabon's short-story collection Werewolves in their Youth during one of those drunken late-night bar conversations where you can hardly hear the other person speak over the jukebox, I realized the next day that the book I had read was actually Victor Pelevin's A Werewolf Problem in Central Russia.

But the one kind of book I love above all other things is young-adult fantasy and when Michael Chabon published a book called Summerland that could have been hand-crafted by highly skilled psychic artisans in exact response to my dream-book specifications, I picked it off the shelf at the store and paid for it and went home and read it at once. And it was a work of genius, a brilliant and beautifully written fiction for readers of all ages that I found more interesting and more pleasing and more complex and altogether more delightful than almost any other book I have ever read.

Summerland showed a close acquaintance with the D'Aulaires' Norse Gods and Giants , a book I renewed from the library every single week of third grade because I couldn't bear the idea of not having it in my possession. I loved everything about that book: the strange words, funny as well as ominous (Niflheim!); the rainbow bridge to Asgard (what can I say, I was an eight-year-old with a pair of X chromosomes and it is not surprising that I liked rainbows); the wolf Fenris (I spent many hours trying to figure out how and why Fenris also made an appearance in the Chronicles of Narnia, it was a fact no less mind-bending than the way that the characters in Madeleine L'Engle's books about the Austin family had somehow actually read her Wrinkle in Time series). In my favorite story, Thor bets he can drink more than any man in the hall of the Jotun Utgardsloki, but when he takes a deep draught (I loved the word "draught") from the drinking-horn he is surprised to find it almost as full as before; it turns out that the tip of the drinking-horn reaches down all the way into the sea. Thor has caused the oceans to ebb with his thirst. (The D'Aulaires' book has recently been re-released in the children's collection of the New York Review of Books, with a very good preface by Chabon himself.)

In short, I loved Summerland , I got all of Chabon's other books and read them and loved them also and he found a place on my list of most-favorite writers, people whose novels I buy in hardcover the instant they come out without carping about the cost. Thus The Yiddish Policemen's Union , just as entrancing as Chabon's earlier books and enticingly set in an alternate-history version of 1940s Alaska settled by Jewish refugees (in the world of the novel, there is no such place as Israel).

It wasn't until I was eating a late dinner (English-muffin pizza, something I learned to make as a small child in Montessori school and still fall back on when I'm low on groceries—if you keep them in the fridge, English muffins stay edible if not exactly fresh for an amazingly long time) that a certain uneasiness came over me.

Hadn't I read somewhere recently that the publication of Chabon's new novel had been delayed? He had announced on his website that the book had been rushed into the publishers' hands without sufficient time for editing, and though it meant canceling tour dates and pushing back the publication date from spring 2006 to winter 2007 he had decided to take more time for the good of the book. Which made tons of sense.

Yet this novel bore none of the signs of having been rushed into production. (If you want to know what some of those are, read Zadie Smith's On Beauty.) It was perfect in every respect.

I pushed away my plate—the food had somehow become cold and lumpy in my stomach, I didn't think I'd be able to swallow the rest of the second muffin half—and went to the computer to see what was up.

What was up was that the book I had just read did not exist.

It was still on the Amazon website with an April 2006 publication date, but this was January, not April, and even the April date had clearly been superseded, Chabon's author site made that very clear.

I had just read an imaginary book.

Was I hallucinating?

The book looked perfectly ordinary from the outside. It had blurbs from Philip Roth and Thomas Keneally and Michael Moorcock and a slightly over-the-top author photo covering the whole back cover. I opened to the title page and flipped it over.

Copyright © 2007.

It was only January 2006. You might get a book in December that had the next year's date on it, especially if you'd wangled an advance copy from the publicist. But no publisher would print books with the copyright dated a full year in advance.

The next day I went to the best independent bookstore in the area, where I was told that the novel's publication date had definitely been pushed back to 2007 and encouraged to purchase one of Chabon's existing novels in paperback.

For a day or two I felt pretty strange. But I soon decided to keep it to myself. If I was losing my mind, this was after all an exceptionally pleasant way to do so. And what I found over the next few months was that if I sat down at the computer in the right state of bleary-eyed mental receptivity, opening my mind up to what I most wanted to read in the world and sticking a book in the cart without looking too closely, I was sure to get something good.

In this way I obtained Jonathan Lethem's massive and totally heartbreaking novel about Stanley Kubrick and Neil Gaiman's hilarious and yet also outrageously moving tale about the Wild Boy of Aveyron (the cover had blurbs from J. M. Coetzee and Margaret Atwood and a sticker proclaiming it the winner of the Booker Prize for 2009) and Robin McKinley's sequel to the vampire novel Sunshine. (It wasn't a sequel, actually, more like a prequel about the heroine Rae's father set twenty-some years before Sunshine begins, bearing a roughly comparable relation to that book as The Hero and the Crown does to The Blue Sword , but it was absolutely delightful and I wasn't going to complain about it, was I?)

After a little while I realized it could work for dead authors as well as living ones. I got the last novel in Rebecca West's tetralogy, the series that begins with The Fountain Overflows (my favorite novel of all time) and continues through two—now three, I guess you'd have to say—posthumously published volumes. I got Byron's Memoirs , and they were even funnier and more amazing than his letters. I got a complete set of the works of Jane Austen in twenty-three volumes.

I am reclusive at the best of times, and also somewhat secretive, and though I couldn't explain it (well, if you've ever read a fairy tale, you can imagine what was going through my head) I had a feeling that the strange gift I had been given, my access to this other Amazon, could be taken away just as easily as it had been visited upon me. That exposing it to the cold light of reason—or to friends' skepticism and mockery—could do no good. Wary at first that the books I received from the other Amazon might be as addictive as the Turkish delight Edmund gets from the White Witch, moreover, I soon consoled myself with the thought that books from regular Amazon or from the library continued to captivate me as well. In other words, I was already addicted to reading.

Then my friend Leif came to town for a conference. (I had known him for some months before I realized his name was not Leaf, his fair hair should have tipped me off to his Scandinavian ancestry but he had misleadingly been brought up by hippies in a geodesic dome in the Pacific Northwest so it was a very natural mistake.) Leif had a hotel room for the first two nights of his trip, but he worked for a worthy non-profit that kept costs down wherever possible, in this case by expecting him to find his own lodging for the Saturday-night layover that would make his flight affordable.

As a compulsive reader and writer and all-round workaholic I generally avoid having visitors, but sometimes you can't say no. I inflated the Aerobed and put the sheets on with a familiar mixture of anticipation and bitterness, I liked Leif and I had stayed at his apartment in San Francisco for almost a week two summers ago but it nonetheless makes me slightly crazy to have visitors. The place gets all cluttered up (I am too lazy to deflate and reinflate the bed, for instance, so it gets propped up against the wall during the day, sheets and all) and it seriously cuts into my reading and writing time.

"What is this?" he said late Saturday night, plucking a book from the shelf and beginning to look through it. We had eaten Thai food and drunk a lot of beer and now we were finishing the last part of a bottle of Scotch that one of my students had given me the semester before. I had smoked three of his cigarettes and was not very happy about this tobacco recidivism.

I saw the volume in his hand and flinched. It was one of the Austen novels—I can't remember now which one— Alice and Adela , maybe, or possibly Self-Possession (my favorite, I think, out of the ones I hadn't read before).

He looked at me.

"What's going on?" he asked. "Should I know what this is?"

I had forgotten that Leif was a Janeite. In general he only read worthy books about the destruction of the environment and socialist politics and various kinds of injustice, but he had a passion for Austen's novels, indeed he read them all again every year and had a huge collection of Austen movie adaptations on DVD.

If I had remembered, I would have hidden the books in the back of a closet where he would never have seen them. It was too late for that now. Also I was drunk. Also it was a long time now of not having told anybody about this incredibly cool thing that was happening to me. It's like having an affair with a married man. At first it's exciting keeping it to yourself. Then it becomes burdensome. Finally you're basically dying for a chance to unload your story, and you just have to hope the floodgates open when you're in the company of someone trustworthy.

I explained it all to Leif in more or less the same way I've just explained it here, only more drunkenly. I was rather rambling and discursive and he several times had to bring me back to the point. We drank more whisky. Meanwhile he was getting more and more excited.

"Don't you see, though?" he said, getting up and starting to pace around the apartment.

I could see he was excited, but I couldn't see what about.

"You'll be able to do all sorts of things with this!"

"Like what?" I asked.

"You've got a responsibility ," he said. "You've got the ability to change history, in a roundabout way at least. You could order a book called, say, ‘What Brought Bush Down.' Or ‘Saving the Polar Ice-Caps.' Or ‘The Triumph of Alternate Energy in the United States.' And the world would come into alignment with it, wouldn't it?"

I stopped and thought about this. I wasn't sure he was right—the idea that Neil Gaiman would win the Booker Prize in 2009 seemed more wish-fulfilling than likely, though of course the right committee might see why it was such a good idea—but on the other hand I could sort of see where Leif was coming from.

There was one obvious problem, though.

"I don't think you understand," I said. I was really pretty drunk at this point, so I wasn't at all ashamed. "I mean, I don't have the vaguest idea how this works, but one thing I know is that I have to really want the book."

"But how could you not want to read a book called ‘The End of Republican Hegemony in the United States,' especially if it might have some predictive power?" Leif asked (you could see he meant every word of it, too).

I hated to pop the bubble, but it had to be done.

"Leif," I said.

"What?"

"What kinds of book do I like reading?"

He glanced along the shelves next to him. It wasn't really his kind of question. "Uh, novels?" he said.

"Novels. A lot of novels. Some literary biographies, and some popular science books. But almost entirely novels."

"But you could still get excited about the reversal of global warming, couldn't you?"

I was forced to confess that there was absolutely no chance of me mustering the level of excitement necessary to summon a book about the reversal of global warming from the other Amazon. (I didn't even want to read the ones they had at regular Amazon, for god's sake.)

When he finally got it, his face fell. Really, literally: the muscles got all droopy and sad.

"But there must be something you could get," he said, "something that would make a difference in the world."

"Like what?"

He cast about for a minute. Then he said the name of a well-known advocate of sociobiology, someone I have often described as the hatchet-man of evolutionary psychology (I could hardly stand to say his name, I disliked his opinions so much), someone I talk about obsessively (that's obsessive hatred, not obsessive love) to anyone who will listen.

"What about him?" I asked.

"Well, what if you got hold of his memoir and it was called something like ‘How I Learned to Hate Evolutionary Psychology and Decided Women are Just As Good As Men and Subsequently Channeled My Energies into Explaining Why Nurture Often Trumps Nature, Thereby Persuading the Government to Put Vast Sums Into Public Education'. . . ."

"That's a pretty awful book title," I said, but I felt a twinge of curiosity. I also felt drunk, tired and nicotine-poisoned. I got up and poured the last of the whisky into my glass, topping it up with cold water from the tap. I didn't offer any to Leif.

"Well, you're the writer, you come up with something better. Don't lie to me, though; I know you want to read that book."

And we went into the other room and I sat down at the computer and Leif annoyingly hung over my shoulder giving me instructions I didn't need and five days later I received a package that when I opened it turned out to include the hatchet-man's recantation in the form of a memoir titled Here I Stand (an allusion, I thought, to a famous passage in the writings of Martin Luther). And I spent the evening reading it and it was pretty great and I put it down with a smile on my face (I completely agreed with everything he was saying, I especially liked the way he abased himself in his lavish repentance for that former identity as high-profile apologist for genetic determinism) and I went into the other room to check my e-mail.

One of my students had sent me a link to a news story. I clicked through to CNN.com and learned there that the hatchet-man had been hospitalized earlier that evening.

I told myself it was nothing to do with me.

But I couldn't sleep. I kept checking the news, and around 8:40 the next morning the AP said that the hatchet-man was dead of a cerebral aneurysm.

Had I done a violence to this man?

Over the next few days I became increasingly certain that my reading his words—or at least the words I had somehow caused to be printed with his name affixed to them—had actually killed the man. His brain must have rebelled, it seemed to me, at the incompatibility of his real-world beliefs and the ideas espoused in the book that had come into my possession.

When Leif asked me about it, I laughed off the story of the other Amazon and said pious words about the hatchet-man of late lamented memory (and I felt relatively unroubled doing it, a few years earlier Time had printed the hatchet-man's lavish and completely disingenuous eulogy for a man he was known to have considered the avatar of fuzzy thinking and wrong-headedness and so it was both [a] only fair and [b] common politeness). It was easy to persuade my friend that it had all been an elaborate hoax. In any case, Leif didn't really want his idea of Austen devastated by a larger canon. He didn't care about novels otherwise. Probably he was so drunk that night, it all seemed like a dream.

If you're expecting a Faustian twist at this point, a fit of repentance on my part or something like that, forget about it. The only difference now is that I pay off my credit card in full every month. This is possible because of a large infusion of cash that came my way when I was commissioned to write a book—this is no joke, the agent approached me a week or two later, we sent out my proposal a month afterwards and following a successful three-way auction I signed the contracts in September—critiquing the hatchet-man's writings and the whole school of evolutionary psychology.

The book's coming along well. I've been very careful so far not to plagiarize from the memoir, it doesn't seem fair, but I am certainly finding it an extremely helpful resource. $112.78 at the other Amazon is the exact same thing as $112.78 at the regular one, I have learned, except that I now own, among other things, a brand-new Penguin edition of The Mystery of Edwin Drood , Dickens' fourth-to-last novel and one of my favorites. People who call it a minor work have never read the amazing ending.

The conclusion turns out to be more or less totally sublime, Dickens does the whole divided self thing even better than Robert Louis Stevenson (Jasper killed Drood while the opium fit was upon him, but lacking any memory of it became convinced of Neville's guilt—somehow Jasper's being in the grip of these uncontrollable desires and compulsions makes him perversely more sympathetic than any of the good guys). The real satisfaction, though, lies in seeing what happens with the minor characters. I have always been half in love with Mr. Sapsea and his wife's tombstone, with stone-working Durdles (he has "Tombatism" instead of rheumatism!) and his stone-throwing Deputy, and those stones and tombs lead directly to Jasper's exposure in the cathedral burial-ground. By the way, although there's something absurdly compelling about Dickens's awful heroines (I feel the psychological pull of that sort of heroinedom), surely in the end it's safer—more permanent —to play a minor role than a major one, to be the person whose modest action at the periphery of the drama tweaks a strand elsewhere so as to give the sense of an ending?