One thing you may find useful is to look at member activity on the CC page. This will give you some idea of how much forum activity there is. Sometimes topic titles can be telling. "Thinking of Quitting" or "Listen up people, you know who you are" (Yikes - I have seen similar.) There are a few clubs out there that use off WGT forums, so this wouldn't be that helpful.
A look at the roster can provide some info. I remember when I was shopping for a new CC, I noted one that had several Hack 150 average players as members. Defo a red flag.
If you're into a specific type of game, A/S, plain tourneys, or whatever, a look at the activity of the owner and directors might be a good clue.
Once you've narrowed it down, you can go the wall or friend/PM route.
Good luck in your search. Finding the right CC is a big plus.