Yep, rec.games.pinball newsgroup is really active, and lots of good, helpful people there. I haven't found any good forums other than that, I look once a month or so at vpforums but there isn't that much there on real pins.
I just picked up my first pin, a Twilight Zone, a few weeks ago. Its in about a hundred pieces right now, while I clean it, replace a few targets & plastics, and rebuild a flipper. Its amazing how much dirt there is that you can't see until you take the machine apart.