did you see those "prequel" novels for I,Robot that came out not that long ago? I think its a trilogythesilentman said:I went back to read some Issac Asimov. Currently on I, Robot, and planning to pick up the Federation (uh is that right?) trilogy later on.
Might go back even further and reread some Poe. I'm in the mood for Pit and the Pendulum.
I've read the first...there was some stuff I really liked but it was kind of ruined by the dumb romance, Susan Calvin doesn't swoon dammit! *ugghh*
better seen as a stand alone than related to the original
EDIT: also I think you might mean the "Foundation" books