as previously mentioned, Phillip K. Dick wrote some terrific stories which (for me, anyways) combined the mars/rockets/space optimism of 1940s/50s era Asimov and Bradbury with the growing apathy and anxiety of the 1960s.
also, Harlan Ellison is, for my money, the best sci-fi short story writer of the 1970s (give or take a couple decades). "I Have No Mouth But I Must Scream" is one of the greatest tales of future nihilism ever.
I haven't read any of Michael Moorcock's fantasy shit, but "Final Programme" is among the best of the new wave of sci fi in the 60s. If you like that, there's a whole bunch of other weird novels featuring the same character.
>>18
posted tons of classic must-read novels.