I'm looking for a Rick Wright high definition wallpaper, and I can't find any. If someone runs into one, please let me know. I would appreciate it.

Google Image search "Richard Wright Pink Floyd" and make sure you have it set so that only large images are returned. You should be able to find something that way.

I tried, and couldn't find any.

Then you might be out of luck. There aren't a lot of wallpapers out there of the individual members, but I have found a lot of larger images of the whole band together, from one era or another.