Enhancement pack: should be enough to get you online at least...
Any moment now, Dizzy, the administrator of the next big server (Slave Girls 4), should be posting a thread with the additional download needed to play on his server...
You might want to try this
forum, register for an account there, and join the "Alliance" usergroup (as you plan on flying Fed). This way, you can keep up on the plans etc. for the next server.
There are a couple of voicecomm programs being used by the different teams, once you're in the Alliance forum, they'll provide links etc. to the program of choice. Voicecomms will help you get wingmen to help you when you're on the server.