Take a visit to your local track on a race day and just have a general look around. Ask around for vacancies (especially with small teams).
Starting a race team of your own should not be attempted without experienced advice beforehand and throughout the project (and of course, a small fortune to spend on breakages, write-offs, team costs, etc)
I have just joined a new, small, local race team and we plan to race a Peugeot 106 Rallye (S1) in a small 'Saloon car cup' at Castle Combe in Wiltshire in the U.K. By joining a new race team, I can develop a better understanding of car set-up and tuning by being there through the transformation of the car, from potential rice bowl, to something with a little more purpose. Of course, I will have responsibilities in the team, but most pressure will be on our team leader and driver, making my part that bit easier.
Hope this helps,
Jamie.