Orson Scott Card (Ender's Game)
Anne McCaffrey (Nimisha's Ship, the brainship series, the freedom series, the dragonriders series, crystal singer series)
Dean Koontz (Prodigal Son series)
Orson Scott Card is genius in Ender's Game. I haven't read any of the sequels, but I hear they're just as good or better. Anne McCaffrey's Brainship series is really good, and I recommend the Brain Ships omnibus. It combines Partnership and The Ship Who Searched. Her Crystal Singer series (the first book is Crystal Singer) is also a good series. However, the subsequent books aren't the same level as the first. Dean Koontz's Prodigal Son series is an awesome twist on the Frankenstein story. He really takes it into the hard core sci-fi with this series. But, if you don't care for Koontz, this has the same short dialogue that can leave something to be desired. The storyline itself, however, pulls you in and dumps you with awesome cliff-hanger endings. Good thing is the entire series is available.