Isaac Asimov - Foundation Series, Robot series (I, Robot movie inspired by them), and currently reading Pebble in the Sky
Arthur C Clarke - Rendezvous with Rama and its sequels, The Songs of Distant Earth, 2001: A space odyssey (havent read the sequels), The Fountains of Paradise
Jack McDevitt - The Engines of God and its sequels are great. Think of archaeology, but instead early human cultures, alien cultures, both living and extinct. A real fun read.
Philip K Dick - You may be surprised at how many of his books have been turned into movies. Naturally, the books are better. The one's I've read are:
-Do Androids Dream of Electric Sheep? (Blade Runner)
Some others of his were turned into movies were Next, A Scanner Darkly, Adjustment Bureau, and Paycheck.
Orson scott card - I've only read Ender's Game, none of the sequels, but it was a good book.
I'm pretty big on sci-fi lately, especially hard science fiction ( a bit tougher for some folks to get into), but this is definitely a list to start you off on if you havent read these yet. Asimov and Clarke are musts.