I've started with a team and really don't want to play with them anymore. What can I do?

During the "Friendly's" season, you can simply switch teams. USAV allows for some level of testing the waters, but only before the local season starts. Each region runs with their own timeframe.  The Lonestar region starts in late October/early November and goes through Nationals (in 2010, that's the first week of June).  Once the actual season has started and you've signed up with a club, that's the only club that you can play with.

If you're not sure about a team, talk with their captain/club director. Go to their practice. Go to a tournament as an observer and see whether you want to play with them.  Don't commit (Register w/ the LS USAV and select them as a club) until you've decided that it is definitely the team you want to play with.  Changing teams is possible, but it requires the regional commissioner to sign off on your change.  I have no idea how difficult this is, but it is probably not as simple as requesting a change.