Yup, big fan here!!
I have The Swords of night and day
Drenai Tales Volume 1
Druss the legend
Waylander
Hero in the shadows (I think that's my fav so far)
It's a real shame he died in 2006
Here's a pretty good link:
http://www.fantasticfiction.co.uk/g/david-a-gemmell/