I wouldn't worry too much about joining a team right now.
Instead focus more on getting out to some games and getting to know people in the airsoft community. Eventually you might find a cool group of guys who you'll airsoft with regularly.
Also, being that you're under eighteen, it might be difficult to find people or places that let you play. Some organizers allow younger people people to participate if an adult takes responsibility for them. It'll be really helpful if you can find and older airsofter who can vouch for you at games.
How long's the wait till you're eighteen?
I roll A.Z.T.E.C
^That's where I received my elementary education.