No blog devoted to cupcakes would be worth it's icing sugar without paying homage to Johnny Cupcakes. Now this guy doesn't actually make cupcakes, but he has fantastic t-shirts (and more) that always have some cupcake related thing on them. Some of the designs are limited and become quite the collectors item. You can shop for his stuff online, or if you're in the Boston area you can stop by his flagship store.
I totally wish he made aprons!! Maybe someday :D