As I mentioned before, the letterpress community is small but growing. As I have been searching around, I have stumbled upon many great websites of printers and their work (see snap&tumble).
I recently came across Fugu Fugu Press, located in Pasadena, CA. I love their line of cute characters, and Japanese inspired design.
Fugu Fugu is comprised of a married couple, with their studio outside of an old gas station. They work from an old Heidelberg Press (which I would love to own if I had the space!)
All of their cards are made with recycled paper using soy-based ink. Their cards are now sold worldwide, and you can see what they are currently up to by following their blog.