A few very good Michigan breeders are right here on YT. Check out Signature Yorkies, Greens Tiny Treasures and Keens Canines of Aria (YorkieMom, Breny, Wrenee4). I know there are a couple more as well in the Grand Rapids and Muskegon area, but I can't recall their names!!!!!!
http://www.signatureyorkies.net/ http://www.greenstinytreasures.com/ http://www.keencanines.com/