I dont know of any camps but I have heard several people talk about doing something like it. If you have a boat I would think you might be able to hook up with a good rider/instructor up there that would be willing to go out one on one for some tips and teaching. I would prefer this myself because you could learn a lot more than going to a camp with a bunch of people for a week. I guess you wouldnt have the social aspect that a camp offers.
If it were me I would try to get a few friends together and pitch in some $$ to get a pro in the area to go out with you for two or three days. You would have a blast with your friends. I have also found that when you go out with friends you really push and challenge each other to learning new things. You might get lucky and find someone that is willing to take you on their boat for the training.
We will be running weeklong camps next Summer in the Delta with Derek Conway & Kevin Bird as the main instructors along with Criss Dykmans(hopefully) fot 2 days a week. It will be a houseboat cruise to differant parts of the Delta. It will also feature many of the National CWB riders as guest instructors. Email me if you want more info.