Does anyone know where I can find designs similar to pro football teams such as the Denver Brocos or Indianapolis Colts?
My bet is those are copyrighted designs and you won't find them for sale.
We were making a machine embroidery quilt in a class, and the instructor was creating the designs. She said that she could not use the phrase "Super Bowl" (we had the Super Bowl in town that year), and had to substitute "The Big Game" for it b/c it is copyrighted. You can't even legally try to reproduce the team names with the font they use (how I know this is a long story I won't get into here), although I suppose for your own use it would be ok. You can just use a football, however; they haven't copyrighted that (yet)!
MSU: I can help you find these. email me.