AWWWWWW i am sorry, He is so cute too and i left him a bone. I don't no about the states but here in Canada a contract consist of any party signing a legal binding contract. I think you should take him to small claims court. Also how much more did he want for the pup and how much was his asking price that you paid him.
I am truly sorry. I wish you better luck. Don't feel blue your pup is out there just waiting to come home and love you and be your best friend.
