Dog Breeders Map List- The Yorkshire Terrier Club of America
E WA didn't have any breeders listed at YTCA, W WA has breeders listed.
You could try petfinder.com also, rescue, shelters.... I can't recall exactly, might have been Sprague Lake shelter had a yorkie about a month ago, I'm sure that one is in a new home, just an example that yorkies do make it into the shelters in E WA, E O and ID. Yakima humane society ships strays to Seattle's shelter fairly often I understand.