He'd written about two dozen novels before his untimely death in 1996, but an amazing writer with both a gifted imagination and gift for words. I was never bored reading any of his books.
My favorites are:
Han Solo Trilogy: The best Star Wars novels, hands down.
Adventures of Alacrity Fitzhugh and Hobart Floyt: Fun space opera trilogy with lots of heart, amazing back story and plenty of action. Sadly, out of print but easy enough to obtain 99cent copies online.
GammaLAW: Epic science fiction series about a group of super soldiers sent to a distant world that has fallen out of communication with the rest of the settled worlds hoping to solve the mystery of an alien race threatening mass invasion. He once likened GammaLAW to 'War and Peace in space, with a cast of characters in the hundreds', he was working on the manuscript at the time of his passing, and his longtime friend and pseudonym sharing author, James Luceno, pulled the final script together which was released in 4 paperbacks in the late 1990's. Sadly, also out of print.
Other fun things he worked on were the novelizations of (and serious improvements on) the Harmony Gold Robotech animated television series, where apparently he and Jim Luceno took turns writing 3 books each of the initial 12 book series and alternating on the 5-book Sentinels novels and writing each section of the final 'wrap-up' novel.
The tongue-in-cheek Black Hole Travel Agency quartet of novels show how far out he and Jim could go in their world building and plot scenarios, which is pretty far out.
I've never found a comparable author that I have enjoyed to read so much, and I sure have tried. Iain Banks is as close as I've gotten, but he still falls short in the storytelling, humor and wit departments.