I've had a couple people ask me about ideas for growing (as opposed to starting) a SQL user group. While it's definitely a lot about content, formula, and presentation, it's just like running a business, it all comes back to marketing. That said, here are a few suggestions:

• Ask PASS to email everyone in your area. They won't (and shouldn't) give you the list directly, but they can do a one time intro email to those in your area and then run announcements about upcoming events in the bi-weekly newsletter.
• Submit each meeting to the big community sites (SQLTeam, SQL-Server-Performance, SSC), they will usually advertise them for you
• Contact the IT chair of any local colleges
• Get to know the leader of the closest .Net user group and the nearest INETA mentor
• Get to know the nearest MS Developer Evangelist. They are typically very good at helping you network with other groups. Here in Fla Joe Healy has been my contact and has really been helpful.
• Contact as many local staffing companies as you can. They all want to meet more prospects and they always appreciate a reason to email/talk to their existing client base. They are more than happy to advertise your event (and probably buy the pizza too!)
• Ask every member that attends to tell one new member about the group. Remember that not everyone will attend every time, so focus on growing the mailing list AND attendance
• Don't forget to get to know all the other groups. Other SQL groups in the same state, other types of computer groups, all are usually willing to post your event (and vice versa)

Most of us running groups dream of the day the group is self sustaining. Can't say we've reached that state in Orlando or that we've got it all figured out either. Drop me a note if you've got other ideas, always room for more.