twilightsm was looking for post- or peri-apocalyptic books, and also dystopias. imtboo pointed me at zir post, and I wrote the following. So I thought I'd share.

Oo, clever thought: look at the post-apocalyptic LibraryThing tag. That's a good start. Off the top of that list, I would especially recommend Canticle for Leibowitz and Riddley Walker as spectacular.

Also the dystopia tag is pretty good. You must read Handmaid's Tale and Parable of the Sower.

Um, glancing at the books near my desk for a start:

Queen City Jazz by Kathleen Ann Goonan; an SF novel about nanotech
A Language Older Than Words by Derrick Jensen. Non-fiction essays about the ongoing human destruction of the planet.
Stand on Zanzibar, by John Brunner. Definitely one of those "as the world is ending" peri-apocalyptic books. Also freakishly prescient.
Pretty much anything by James Morrow.
Good Omens, by Terry Pratchett and Neil Gaiman. Very funny take on the Apocalypse.
Always Coming Home, by Ursula K. Le Guin: a post-apocalyptic half-novel half-anthropology of a new community after our own.
The Dispossessed, also by Ursula K. Le Guin. A classic pair of dystopian societies in second-wave feminist SF.

Comics and illustrated books:

Baaa by David Macaulay. Also Motel of the Mysteries, by the same. Both satirical with lots of illustrations.
The System, by Peter Kuper. Wordless and beautiful and very very scary. Set in Manhattan, just before the bomb goes off. Written before September 11, also freakishly prescient.
Watchmen by Alan Moore, and Dark Knight Returns, by Frank Miller; modern classics in their post-apocalyptic re-visionings of the superhero genre. Spoiler: superheroes are the cause and the effects of the apocalypse. (Otherwise stay the heck away from superheroes, as a rule: many of the superhero books thematically deriving from these two have degenerated into thinly veiled snuff and rape porn.)
Give Me Liberty, by Frank Miller. Vaguely Objectivist Dystopian SF. Sequels are not so vague.
V for Vendetta by Alan Moore. The comic is wordier and more subtle but not as pretty as the movie.
DMZ, by Brian Wood; protagonist is a reporter in Manhattan, the DMZ between the Free States (Michigan, Upstate NY) and the New United States Government. Most Manhattanites live in the line of free-fire. Actually, many by Brian Wood: Channel Zero, Couscous Express, The Couriers.
Glacial Period, by Nicolas de Crécy. The Louvre is rediscovered by explorers excavating the Lost Continent of Europa.

phew, that's a lot. Probably more than you need. If this whets your appetite in a particular direction, ask me and I'm happy to go into more detail!