Yea, I would have thought we did too, but I couldn't find it either. Okay, I've set it up. Here's the link:
http://www.last.fm/group/Tilted%20Scrobbler%20Project
I've made it 'Member Approval' for new members, so we don't get any Tom Dick and Harry showing up. It doesn't track group stats until we have 15 members, so come one, come all!