I know that alot of creep tribes -alongside their freep kin counterparts- have vent, but alot of newer creeps and some -fairly not new- don't have vent. I do not know how many freeps use vent when they are in the moors, but on creepside it is preferred as opposed to ingame. Vent is a lot nicer for voice communication, and if you dont have voice you can sit in and listen for raids and co-operate as normal.
download page: http://www.ventrilo.com/download.php
Click the version of computer/laptop under the Client section that you have and it should take you to a new page which should have a clickable button at the bottom saying 'i agree' click that and it should install vent onto your system!
Setting up vent takes less than a minute.
First thing you need is your name -preferably an ingame name people will recognise you with- to do this press the arrow that looks like this (->) type in your name, and thats it!
When you are asked to join vent, you probably won't have the correct details to enter the specific server, so, all you need to do is ask, and someone in the vent will give you the:
A) vent 'server address'
b) the port number
c) if there is one, a password.
to enter these, click the little arrow (->) below the section you created your name at which should say 'server' and a menu comes up where you fill out these details in the a/b/c order listed above.
Once these details are filled out, hit OK, a message should come up on your vent screen saying,
MSG: Server is available. Press connect.
Connect is at the right hand side of the vent page.
Thats it! Your vent is set up and ready to go, there are other things you can do in vent, i.e if someone is too loud turn them down and vice versa, but once you go through the options a few times you will get used to it and know what you are doing
If your stuck feel free to ask me, or anyone else in vent how to change something, and im sure they will tell you.
If for some reason Vent doesn't download, ask someone again and they will try to help as best they can