"I'm not too interested in Roadfly.org (bimmer.org). Their interface is awful, which means that they just don't get it in my opinion... "
Yeah, the interface is awful. In fact, it is worse!! Hurry up and convince them to be accumulated by Wayne's Empire and give me a proper interface!!
You could probably get
www.bmw2002faq.com for nothing - the dude appears to be constantly on the edge of his finances.
Trying to be constructive, you need to think carefully about how you will retain the BBSers of whatever you are interested in.. you wouldn't want to pay over $$$ and see them disaffected and disappearing.