As per our discussion at the Edmonton Chapter meeting, you can find information about the Northern Alberta 4WD Association at http://www.na4wda.org. It would be great to have more Hummer owners there, as they sometimes give us a rough time. (It's all fun, though. They're a great group of people, with a couple exceptions.)
If you have any questions or concerns, they should be able to be addressed in their forums, but you can run any by me here. A couple other CHC members are NA4WDA members and should be able to help you out here too.