The Harplist is a Yahoo Group (email-noticeboard, sort of like a newsgroup) though the moderator likes to vet new applicants (not as fierce as it sounds: she was getting a lot of cruisers who weren't really interested in harp and who just joined because they thought it seemed exotic). As this list has around 1000 members she wants to keep it from getting out of hand. There are also separate Yahoo groups for Wire Strung harp, Pedal Harp, Cross-Strung Harp and several more, but Harplist is the main one and most of the members of these smaller groups also belong to it. It's very active and interesting, a great resource for players of all types of harp, with a lot of expertise among its members to draw upon.
If you go to www.yahoogroups.com and follow the instructions it should lead you to these, though the harp list goes by a different name - can't remember what, but it's pretty obvious. PM me if you have problems!