Non military books? That really stumped me for a solid few minutes!
A very short list but these have come to mind as memorable.
Wiseguy by Nicholas Pileggi (as good as and in some ways better than the movie adaptation Goodfellas/ more stories and facinating details)
Siddhartha by Hermann Hesse
The Alcoholic Republic: An American Tradition by W.J. Rorabaugh
The Bridge on the Drina by Ivo Andric
2001: A Space Odyssey by Arthur C. Clarke
Slaughter-House Five by Kurt Vonnegut
The Little Prince by Antoine de Saint-Exupéry
North by Northwestern: A Seafaring Family on Deadly Alaskan Waters
by Sig Hansen