Sci-fi:
Dan Simmons: Hyperion, Return to Hyperion; Ilium, Olympos
Tobias Buckell: Crystal Rain, Ragamuffin, Sly Mongoose
Roger Zelazny: Lord of Light
John Scalzi: Old Man's War, The Ghost Brigades
Ian M. Banks: really any of the Culture novels (Player of Games, Use of Weapons, etc); The Algebraist

Fantasy:
Ken Scholes: Lamentation, Canticle
Guy Gavriel Kay: Tigana, Lions of Al-Rassen
R. Scott Bakker: The Prince of Nothing Trilogy, The Judging Eye
C.S. Friedman: The Coldfire Trilogy
Scott Lynch: The Lies of Locke Lamora, Red Seas Under Red Skies
Steven Erikson: Malazan: Book of the Fallen series

Speculative Fiction:
China Mieville: Perdido Street Station, The Scar
Neal Stephenson: Anathem, Cryptonomicon
Neil Gaiman: The Graveyard Book, Neverwhere, Stardust
Dan Simmons: The Terror
Jim Butcher: The Dresden Files novels


There! Those are just a few names and titles that you should look for when you're looking to buy books.