I've never actually used them, but we produced television commercials for a national chain called "Embroid Me" (yes, terrible name) who does just that.
I know they have several hundred locations, maybe one is near you. As I said we've never actually used them, but our art director did create a whole bunch of fake logos for fake companies and they then took that artwork and created logoed shirts for use as props in the commercial. They looked pretty good.
Or you can contact me directly at
mhancock at oswaldcommunications.com (replace "at" with @, naturally). We do both embroidery and screen printing in house and can put your logo on just about anything you want--jackets, hats, tshirts, mugs, bobblehead dolls, etc...
All we need if your logo in .eps format or we can rebuild it if you don't have it vectorized. Because we do everything in-house we can do orders of a few items to 1,000+. Whatever you need.