As a player, what do I have to do to join a USAV team?

As a player, playing in the USAV is really quite simple.

Find a team that you want to play on and that has said they have space for you.

Register with the USAV via their website (click on "Registration") and select the team that you're going to be playing on.  Send a check for $30 to the commissioner or give one to your team/club director, if they are handling all the USAV registration fees.

Now you're registered with the USAV and are eligible for play with that team.

If you register prior to the start of the official season (during the "Friendly's" tournaments), you can select "Undecided" for your club and play on any team that wants you. It's a great way to get to know who you are going to play with.