Are there any training schools or camps out there that teach the stuff. I mean at an old man -- beginner level? 
Sort of, but not in the U.S. It was originally based in France (obviously, since Belle's from France) and has spread to Japan and across Europe but most groups are pretty informal. Also, belle has left the group he started and already split with Sebastien Foucan (the guy he started Parkour with and who was in Casino Royale). So I believe he's no longer running the organization. Sebastien started "Free Running" and I believe he's left that as well but may be running something else now.
As for doing it in the U.S., your best bet is to download one of the youtube videos that shows people doing the diff. exercises and just find a good park to try it yourself. That's really how most of these kids learn it.
NOTE: One other thing. When you're learning the move, make everything a regression. This is the best way to learn this stuff. For example, if you want to be able to flip off a wall in a cartwheel-kick, you'd do this:
1. Learn to do a cartwheel in both directions
2. Learn to do a cartwheel off a 1-foot high block
3. Learn to do a 1-handed cartwheel off a 1-foot-high block (with leading hand)
4. Learn to do a 1-handed cartwheel off a 1-foot-high block (with back hand)
5. Learn to do a cartwheel, no handed, off 1-foot high block
So you've regressed the move and learned it in parts. You'll do that with everything you see them do, and then it gets a LOT easier to learn.
