You'll need to organise it as an event on a Steam group. It looks like you and Darkness are administrators of "AvP Galaxy Fans Unite" so I suggest posting the event(s) there, since 3 out of 4 of those games are played on Steam and you're going to have a limited showing if you only publicise about it here.
You're free to use my TS3 server to communicate, if you wish. There are separate lobbies for AvP Classic, AvP 2, AvP 2010, and A:CM. Server name is
ts68.teamspeak3.com:7909 and password is "xenomorph" (without the quotes). Otherwise, I think the Steam group chat can be used for voice communication.
As for me, I will be happy to kick ass in AvP Classic. I'll play DM or TDM in AvP 2. I'd have to re-install AvP 2010 for survival, which is, admittedly, probably the most fun you can have in that game's multiplayer. I won't touch A:CM with a twenty-metre pole.