My son Mason draws wonderful pictures and he also paints wonderful pictures. We came up with the idea to put his "crab" on a t-shirt and I tried screen printing for the first time. It was a lot of fun and a huge mess. So, we made them for our boys, and their uncles and their friends. They became a really big hit so I made more and listed them for sale on Etsy. We have sold a few and now I have found this site http://www.cafepress.com/masonscreations to make them.
It has worked out really well because they do the printing themselves and keep the inventory. I just had to come up with the pictures and set them up on the t-shirts. We have ordered a baseball shirt and a baseball cap so far and we really like the quality and the print.