Harry Potter Forums
- Community and bulletin board dedicated to the books and films of the J.K. Rowling series.
- http://www.potterforums.com

The Leaky Cauldron
- Forum for the discussion of Hogwarts, the books, movies, theories and characters.
- http://s3.invisionfree.com/leakycauldron/

The Final Horcrux
- Forum for the discussion of book six and book seven.
- http://www.maturepotter.com

The Cauldron Corner
- A messageboard dedicated to the Harry Potter series. Mostly dealing with RPs, there are also boards to discuss the series and many other topics as well.
- http://theccorner.proboards30.com/index.cgi

Harry Potter's Mystik Merchant
- Message board on the books, movie and characters as well as game cheats, codes and tips.
- http://www.harry4ever.com/community/

Harry Potter for Grownups
- Group dedicated to in-depth discussions of the Harry Potter books, mainly intended for grownups.
- http://groups.yahoo.com/group/HPforGrownups/

Yahoo! Groups
- Harry Potter related online clubs with fan fiction and role playing games.
- http://dir.groups.yahoo.com/dir/Entertainment___Arts/Humanities/Books_and_Writing/Genres/Children's/Authors/Rowling,_J.K.

Trelawney's Harry Potter Club Page
- Book club which meets at Susquehanna County Library in Montrose, Pennsylvania.
- http://susqcolibrary.org/kids/HPCLUB.HTM