I'm very happy to see that the quality of imprints from places like Zazzle, Cafe Press, and Printfection has improved as much as it has over the last several years. I have to admit that I was more than a little disappointed when I first saw, touched, wore a CafePress garment printed with my artwork. It had a plastic sheen to it which never really went away. Reminded me of iron-on t-shirts from the 70s. The new garment printers have it down - color reproduction is entirely in the ball park (from what I've seen, better than that, actually).
Zazzle is especially cool because you get to see what your garment looks like on a person.
CafePress is the old standby, lots of new products of very good quality
I call my
Printfection store Vectorosity - focused on jazz and tropical flowers
More to come