When I started, I found a local screen printer that would burn new screens for $10 a pop. I then owned the screens, and if I even wanted to use a diffrent printer, or screen the shirts myself I could take the screens. He kept the screens at his shop and I just called in orders over the phone. Quite often he would even drop the shirts off for me once they where ready. I never waited more than a month or two to order new t-shirts though.
I would suggest to just start going throught the yellow pages, and call every screen printer listed... You can ask thinkg like:
How much to burn a new screen?
Do I own the screen, or do you?
How much per shirt?
Whats your minmun order size?
Can you give me a price break at a certain quanity?
Can you give me a price beak if I order xx shirts for xx months?