I have a 12 year old one from FireMnt kennels. I can't say enough good about them.
I will definitely get another eventually. Hannah has never been a healthy dog but she's a fluke, they tend to be pretty healthy dogs. I do worry about their knees though, they tend like most terriers to have pretty straight knees.
I have my eye on a few kennels here and there, these are two of them:
http://imageevent.com/ratpkken;jsessionid=26jgn16to1.tiger_s
http://imageevent.com/pecatonica
I have owned 2 and dealt with a few others, do you have any specific questions?