I would google the Yorkie club of amErica and try to fond a breeder that way. Yorkies are a breed that are bred a dime a dozen by people who are looking to make money. At least if you find a breeder on the breed clubs website you have more of a guarantee that you will get a well bred, healthy puppy.
Stay away from breeders that advertise teacup or tiny toy sized yorkies, rare colored yorkies. Find out what diseases and find a breeder who gives at least a 2 year health guarantee against those diseases. Rule of thumb...... You pay a good breeder a decent amt of money for a puppy or you find a cheap breeder and pay a vet a decent amount of money through the life of your puppy