Isaac Asimov is a must if you're doing science fiction. He wrote the Foundation series, as well as several other really good stories, one of my favorites being Nightfall.
Another good author to look at is Michael Crichton if you're looking for a newer author. He wrote Sphere, Congo, Eaters of the Dead, Jurassic Park, and was also the producer for the show ER.
There's tons of other things in the genre. Basically, the only rules are Clarke's three laws, but even then, mainly the third: any sufficiently advanced technology is indistinguishable from magic.