I think you'll find quite a few people here who also have BMW's. I have a '94 325i here's a few pics.
http://homestead.juno.com/firnhaber/files/325i_1.jpg
http://homestead.juno.com/firnhaber/files/325i_2.jpg
There's a great BBS for E36's here's the link.
http://forums.roadfly.com/e36/messages/
the web format is not as good as this one, but it seems more active.
I don't know too many performance sites, I'm keeping mine stock. I've decided not to play with it. (except for some 17" M3 wheels i want to buy) I use it as a daily driver, and to travel for work. Except, of course, when it's nice out then it's all 944.
Mike