uhhh...difficult. Not a single favorite book...thats impossible.
Authors:
Micheal Swanwick: most shortstories; The Iron Dragons Daugther, Stations of the Tide
Frank Herbert: Dune
Gene Wolfe: The Knight/The Wizard Knight
Alfred Bester:Tiger! Tiger! Tiger! (Also known under 'The Stars my Destination')
Mary Gentle: Rats and Gargoyles
Barbara Tuchman: The Guns of August)
Ceasar: Civil War (not meant as 'look how impressive I am' - it truly is an excellent book/autobiography/history/propaganda piece)
John Hemming: The Conquest of the Incas