There are several ways of contacting and interacting with the community of FTB. The main, and probably simplest way is by creating an account on the FTB Forums.
You can also use the official Teamspeak and IRC to contact people, interact with the community and get support.
Teamspeak
Server IP: teamspeak.feed-the-beast.com
Server Password: mcepoch1
IRC
Normally, you can access the IRC by using this link: http://forum.feed-the-beast.com/chat/
However, in you would like to use a different client, or the above link is not working, the server information is below.
Server IP: irc.esper.net
Channel Name: #FTB
Please note: The IRC server is not hosted by FTB, and is subject to the Esper.net rules. We are not responsible for your breaking of these rules.