3 links
CarAudioForum.com
caraudioforum.com
Forum devoted entirely to car audio, review boards and streaming chat.
Glassman's Custom Forum
groups.yahoo.com
A forum dedicated to custom fiber glass work in car audio and entertainment.
Real Car Audio
realcaraudio.com
A portal devoted to car audio. Including forums, instant messenger, reviews, tech center, mobile electronics search engine, and member pages.