If you're interested in joining an fc, the forums for your particular server are a better way to go. Most fcs will advertise on their world forums, and then you can check out people's websites and figure out if you're interested in joining.

It is my personal opinion that the fcs shouting in game, because they have a lower standard for joining, will be of less quality and not last as long as those who make people take 10 minutes to fill out an application and make sure the applicant is a good fit with the shell.