Try his Majipoor books started in the late '70s, one of the best science fantasy series I've come across. Also stories like Dying Inside, Nightwings, Downward To The Earth and Book Of Skulls are worth investigating.But people here seem to be saying that Silverberg wrote his best stuff in the 60-70s. Have anyone else read The Face of the Waters? It was written in 1991. Could you tell me if his earlier books are better?
Never read Face Of The Waters, so I can't commet on that one.