Definitely a little more on the sci-fy end of things but I have really enjoyed:

The Postman by David Brin

The Change Series by SM Sterling (Dies the Fire is the first book)

Both of those were pretty good stories and did a good job of getting me to start thinking about prepping. I have also read most of the above mentioned books and have generally liked and learned from them all.

Not so apocalyptic but I've also enjoyed Alone in the Wilderness by Richard Proenneke (spl?) Neat guy and a good read. For very readable (but a bit dated) general outdoors book I've enjoyed The Complete Walker by Colin Fletcher.
Just a couple of favorites. I'll try and remember some more. Enjoy!


PS: I find it very interesting that so many folks who prep are also big readers. Somehow I find that very comforting and hopeful.