We have 3 Yorkies from an East Coast Rescue League: yorkierescueme.com They work with other rescue leagues (one of our dogs came from TN) and they may be able to refer you to a league in your area. They are very nice and thorough.
I found one league in CO
Welcome to RMYR - Rocky Mountain Yorkie Rescue
Old dog or young dog, boy or girl...once you get that dog you will adore it no matter any imperfections.
Our first Yorkie is a girl with diabetes, food and pollen allergies. She is the alpha and a crazy girl--so compliant that I can shave her tail and check her blood sugar level and she never complains. Our second is a girl who was a breeder at a puppy mill--she is a delight and the sweetest thing--she loves to be spoiled. Our third is a boy who was rescued in TN, where Yorkies are not that popular. He only has one eye due to a birth defect. He is a wonderful rascal who like to find the others treats when they go to get water and he hides them in the dog beds in other rooms of the house.
I have pet allergies, so I would go over to PetSmart and ask people with dogs if I could rub my face on the dogs so see if I was allergic.