If you want to be in a team Sully you have a choice.
1. Find a rubbish team that accepts anyone at the drop of a hat.
2. Learn to drive well, impress a team with your skills, your friendliness and your commitment and be invited into one of the better ones.
3. Form your own team, and build it up until it's respected (e.g. Ocrana) or leave it as an unknown team (erm, I don't remember their names)
But first, ask yourself why you want to be in a team. Is it because of the team spirit? If so, then you need to find a team whos members you like, in which joining is obvious. But if you want to join a team because lots of other people are in a team, or to make you better, then there is no point - you can get fast all by yourself!