Heinlein- the earlier and more juvenile stuff holds together the best, but all is worth reading. I like later novels Friday (tight futurism) and Number of the Beast (more like Stranger). Fave: the admittedly milspec Troopers
William Gibson - Bridge, strand, Zero history, all of it. read it.
Richard K Morgan - Kovacs novels are farking fun adventure sf. Prefect novels are ok as well. He also did a fantasy book with a gay protagonist that showed some spark, can't remember the title, I can handle fantasy as long as it's not too much "Merlin intoned runes from the eldritch scrolls against the troll hordes in books 3, 5 and 9.
Neal Stephenson - Cryptonomicon and System tril. are must read, the rest is ok. liked Anathem.
Gaiman - inconsistent, liked the "Gods". some ok shorts.
Piers, Anne McCaffery, Andre Norton, Asimov (fiction, haven't like his NF and astronomy books as well), I grew up reading their novels and Analog/Asimov's.
Any PK Dick- come on, bladerunner, ya'll.
Rudy rucker - robot books are worth reading and interesting
I want to check out GRR martin after watching game of thrones. seems cool.
Glad to see there's a good amount of SF guys here.