Guys, there is actually a pretty big PK/FR community in Pittsburgh. I'm in the one -- very aptly named, of course -- major group, PKFR. Even besides that, I have randomly seen people practicing at some of my favorite spots. We had a jam here recently that about 20 people came to. In addition, unless there is some other group that was in the city paper, we're the ones that were in it.
I'm personally headed for college come the 30th, but I can give you the number for the guy who organized our group. Usually there is a gym session (we have two gymnastics gyms that let us use their facilities) thursday or saturday every week, and some mini-jam happens about once every two weeks. Some of our members are pretty legit, and they can all teach with some degree of proficiency.
Try 412-651-0665. I'll let him know that some people might be calling within the week.
Also, hint for the wanderers: Try Children's Museum on the north side. Around the stadiums and there is some crazy stuff, but Children's Museum is one of the best spots in the city. It's worth the trip, trust me.
Didn't CMU have a parkour group? I'll look around and get back to you, I know I heard of it.