I wanted to point you in the direction of a great gaming artist, Storn Cook. From what I've seen, his passion and interest in gaming art is largely focused around character sketches. I've browsed through his collections just to get inspiration for NPCs. There are a few times when he has written up stats for them as well, so it makes it easy for me to lift it into my games.
A Sons of Kryos thread with plenty of pics
Recent works on photobucket.