Welcome to the board, Bees. May you find fame and fortune throughout the Gael Serran, and fun and folly in the inns...
The good news is that he isn't dead yet. If you had killed him, the quest would not appear. Head off in the general direction that bsftcs indicated, and if nothing else, just sit -- he WILL hunt you down.
Just be patient, and you'll get 'im. The reveal spell can be a friend with this one... just to see what's moving around on you