I compiled this list a few years ago, and it’s missing a few books since then. I’ll come back and add the ones I missed later.
1) Inferno – Larry Niven, Jerry Pournelle – Fantasy/religious
2) Magic Kingdom for Sale – Terry Brooks – Fantasy
3) Neverwhere – Neil Gaiman – Modern Fantasy (read this now)
4) American Gods – Neil Gaiman – Modern Fantasy
5) Fallen Angels – Larry Niven, Jerry P., Michael Flynn – SF
6) The Adept – Katherine Kurtz & Deborah Harris – Modern Fantasy
7) Homeland – R.A. Salvatore – Fantasy
8) Pawn of Prophecy – David Eddings – Fantasy !
9) Midshipman’s Hope – David Feintuch – SF
10) The Alienist – Calib Carr – Historical Mystery (superb)
11) The Exorcist – William Peter Blatty – Horror
12) Magician’s Apprentice – Raymond E. Feist – Fantasy
13) Jumper – Steven Ghould – Fantasy/Supernatural/Thriller (?)
14) Replay – Ken Grimwood – Fantasy/Supernatural/Thriller (?)
15) Dayworld – Phillip Jose Farmer – SF
16) Songs of Earth and Power – Greg Bear – Modern Fantasy
17) The Truth Machine – James Halperin – SF
18) Apropos of Nothing – Peter David – Funny Fantasy
19) The Cuckoo’s Egg – Cliff Stohl – True Crime (this was like crack for me)
20) Starhunt – David Gerrold – SF
21) Venus – Ben Bova – SF
22) Heart of the Comet – Gregory Benford – SF
23) Sorcerer’s Son – Phyllis Eisenstein – Fantasy (Anything by her, really)
John L. Monk 