Yes, Peter David is a great author. I've had the pleasure of meeting him a couple of times, and getting the first three issues of his run on Supergirl signed.
If you like the Romulans, Diane Duane is writing a TOS series that expands on the Romulans (Rihannsu) from the show. She was given her own continuety to play with, so she has completely free reign.
The first book is called "My Enemy, My Ally"
The second is "The Romulan Way"
the following two are "Swordhunt" and "Honor Blade"
The last book will be "The Empty Chair".
She also wrote a couple of other novels which tie in with this series: "The Wounded Sky" and "Spock's World". I'd recommend reading both before you start on the Romulan series.
"Spock's World" explores the history of Vulcan (and effectively has been written out of continuity by Enterprise), while "The Wounded Sky" litterally takes the Enterprise where no one has gone before.
Finally, she wrote "The Doctor's Orders" which puts McCoy in command of the Enterprise after he gripes about the Captain's orders one time too many - then the captain goes missing!
Two TNG novels - Dark Mirror, a mirror universe novel with the TNG cast and Intellivore, about a sentience eating mystery.
Her emphasis in all these novels is on the characters and not technobabble.
Diane Duane's Star Trek Business page
