I can recommend some good fantasy, but I doubt you'll like what I read And yes, there's a slew of books in the ender's game series. You're local bookstore should have some of them, and at least one will be in the bargain section.

Well there's hitchikers guide. I know fantasy more, but if you go to the fantasy/sci-fi section it'll say what it is on the top of the spine. As a rule, if it looks older and its still on the shelf, its probably good. Bad books, especially paperbacks, don't stay on the shelf.