I thought it would be cool to have a list of books that evoke the Fallout atmosphere. I'll start.

The Road - Cormac McCarthy (Won the Pulitzer Prize in 2007 and is about the journey of a father and his son through a post-apocalyptic wasteland)
A Canticle for Leibowitz - Walter M. Miller, Jr.
Postman - David Brin
On the Beach - Nevil Shute
Treasure of the Sierra Madre - B. Traven (Not post-apocalyptic, but very fitting with the style. The name probably sounds familiar.)
Blood Meridian - Cormac McCarthy (Also not post-apocalyptic, but the extreme violence is very fitting)

I love the Road, also have read On the Beach.

Also try:

(1.). Fahrenheit 451 by Ray Bradbury
(2.). 1984 by George Orwell

Hmm, I honestly don't see any of those as particularly Fallout-like, except for being post-apocalyptic. When I think of Fallout, I think of cartoons from the 80's and 90's. Pinky and the Brain, Transformers (original and Beast Wars), Batman the Animated Series, the X-Men animated series, He-Man, She-Ra, and so on. I mean, the only post-apocalyptic settings I think have any similarity at all to Fallout would be Mad Max.

To me, the fact that the world survived a nuclear holocaust is actually a very minor part of the setting, compared to the general outrageousness that permeates pretty much everything. Take The Master, Super Mutants, The Enclave, even House. I can't look at them without seeing cartoon supervillains. Hell, look at the Enclave and the Super Mutants. Beat them and they'll be back the same time next week with another crazy scheme to take over the world.

So you want a book where a young man/ woman escapes into the wasteland, wanders around with an armoury of weapons, encounters giant animals before saving the country from a group of ex government conspirators?

http://en.wikipedia.org/wiki/%2748. Not post-nuclear, but certainly still post apocalypse.