Have you checked for a breeder in your area at the Yorkshire Terrier club of America site? If not, why don't you go to : http:\\
www.ytca.org
They have alot of valuable info there and can tell you who to contact to find a reputable breeder.
I second the option that "T-Cup" is a good indication of a breeder you want to avoid. I also would suggest avoiding any breeder that takes orders over the internet. Although I like people to email me aout puppies so that their desires and my answers are in writing, I still need to talk to the person and would never take a deposit without talking to the person first.
Good luck in your search.