Well, I didn't really know anyone in town since I'm new here (only here 6 months) so I did a few things:
1) I didn't just make it for webcomic creators, I said comic creators so anyone even working on getting published, or aspiring writers, or artists, or webcomickers like myself could come
2) I went to Meetup.com and got a free membership (you don't have to pay to set up a group unless you have more than 50 members)
3) I set up a group on that site and set up the first meeting for two weeks from that time
4) I made up some flyers with a drawing of mine on them, advertising the group, and went around to all the comic book shops within 50 miles and asked to put them up there
Soon enough, I started getting members. I set up meetings once a month. The first meeting only two people showed up! Felt kind of lonely so neither of them ever came back. Second meeting, same thing. Third meeting though, I had 12 people and that's where my core group of 6 came from. We hang out at a Starbucks or something like that for like two hours and talk about comics, review each other's work, that sort of thing. The writers bring in scripts they've been working on, the artists show their art, and the rest of us give our opinions. It can get pretty fun!