Non-steam is not really an issue, but we still have to recruit you first. I recommend downloading steam anyway so you have a friend list, since that's how we usually bug each other to scrim and such.
http://steamcommunity.com/groups/angryanimalseverywhere is the steam group for Angry Animals, you should be able to find a few players you recognize and try to add them to your friends list. Once we get a few AA to say they like you and want you in, we'll bring you in.