It's probsbly too late for me to post this now, but I have the same problem with my FIL. Same as yours he has everything, and he also likes gold and cooking and baking and carpentry, so every year I buy him stuff for his hobbies.
This year I'm going to give him something that I'm sure he is going to love. click on the link and you'll see:
I Love my granddogs Sweatshirt - CafePress and a dvd with the Story of the Pittsburgh steelers which is his ( and ours) favorite football team.
simple things because he gets the expesive stuff whenever he wants to.