The Three Broomsticks - Penn State University
Atlanta HP an adult Harry Potter group in Atlanta.
Rowling House: Greater Phoenix Chapter Bold text
Don't know if an online group counts, but I'm an administrator on the Babycenter Harry Potter board.
The Poll Castle Commentators! We meet at the comments section of the Poll at TLC. We are about fifty people in number who have been chatting for over six years now.
Harry Potter book club disscusion group in IL