This is the breeder that I got Gracie from. She mentioned to me that they are expecting again in October, so the timing for December should be right. You might want to make contact and get on her list. She is a bit immature as far as doing business goes (on the young side), but she breeds great, healthy dogs and takes very good care of them. Her mother has been breeding Yorkies for years.
http://www.geocities.com/shades_of_iris/PastPups.html
You might have better responsiveness calling rather than contacting via email. She has small children and gets tied up with them.