Here at Day0 we use TeamSpeak 3 for voice communication when gaming.
By using Day0 Teamspeak you automatically agree to the rules at www.day0.com.au/rules.
If you already have Team speak click here or the details are server:ts.day0.com.au
If you don't have TeamSpeak 3 go to http://www.teamspeak.com/?page=downloads and download the client that suits your version of windows.
OK these are the quick and nasty steps to connect to the Day0 TeamSpeak 3 server:
Username: use the name you use in game to avoid confusion