http://www.dickblick.com/
http://www.dharmatrading.com/
There are a number of handmade stamps available on etsy.
I have no idea what I'll do with them but I had to have them:
http://www.etsy.com/shop/Oshiwa?section_id=7621664#
Also, Joann's/Michael's have some (limited) that you can use to try. Probably the smartest way to get a good inexpensive start without investing a mint. You know, like I did. :roll: