If, like me, your weakness is mystery novels, I have some suggestions.

As mentioned above, Michael Nava and his books featuring gay lawyer Henry Rios are one of the best. I was disappointed when he announced he had given up writing and was returning to the law full-time.

Other favourites:

John Morgan Wilson and the Bejamnin Justice series
Joseph Hansen and the Dave Bandstetter series
J.M. Redman and the lesbian Mickey Knight series
Sandra Scoppettone - lesbian PI
Randye Lordon - another lesbian PI
Ellen Hart - The Jane Lawless series is Lesbian
Steven Saylor - Ancient Roman Mysteries - the characters aren't gay, but the author is.

In the ok, but less-than-stellar grouping I'd include:
Grant Michaels
R.D. Zimmerman
Mark Richard Zubro
Kathrine V. Forrest
and a couple of others whose names I can't recall because I finally ditched their books. The Donald Strachey (?) charater. Forgotten the authors name.

Other than mysteries, let me recommend:
The Dreyfus Affair by Pete Lefcourt
Blue Star by Robert Ferro
Dancer from the Dance and Nights in Aruba, both by Andrew Holleran

I have a box of gay fiction I'm chucking - I'll look at it later and see if there are any interesting titles. My books are driving me out of my home - I'm trying to move to ebooks whenever possible.

Cheers,

Mike