I really wanted to have a go at making t-shirts aswell
I came up with some ideas under the name 'Impact Designs'
I looked around for the cheapest places to print onto, maybe screen printing? but I couldnt really find anywhere so I would also like to know (Y)
For blank t-shirts, look on ebay for fruit of the loom (ones tarty bikes use), they sell them quite cheap in packs
One for fresh products
Sorry I cant really help