Here's a place to start...
Yorkies:
http://breeders.net/find.php?breed_i...0031&country=2
Shih Tzus:
http://breeders.net/find.php?breed_i...0031&country=2
This woman is from the Shih Tzu Club of America. She gives referrals to breeders if you call her:
Bonnie La Barbera (IL)
Ph: 847-895-9398
Looks like she is in your area. Here is the site where I got her number:
http://www.shihtzu.org/ASTC/referral.asp?menu=ASTC