The Official EFC Site--This site has a great chat room. I sometimes hang out under the name of 'carillion.' You can also find out when EFC comes on in your area here.
Gene Roddenberry's Philosophy Sphere--This site also has a great chat room, and I'm in a lot, under 'Cari' or 'Carillion.' They have a really fun role-play going there. There's also a lot of really great fanfic.