Sure,
http://www.gibson-talk.com/forum/index.php
http://www.axetalk.com/forum/forum.php
http://www.bluestalk.com/forum/forum.php
http://www.fendertalk.com/forum/forum.php
https://www.gearslutz.com/board/
http://www.harmonycentral.com/forum/forum/guitar
Show More...etc., etc., etc.
"If the support forum is indeed ET's primary communication medium with its customer base, then it is imperative to make its quality as high as the products themselves."