Hi Cocolee,
I'm sorry to hear about your loss. I'm sure you guys gave Coco the best life possible when she was alive. I understand it's difficult to get over, as I myself have lost my first Yorkie in a hit-and-run accident. The driver never stopped and I don't think he knew he even hit my dog. You are not alone.
As for your question about a breeder in the Bay Area. I'm also from Oakland, but I really have no local recommendations. I purchased Otis (current dog) from a breeder in Orange County because at the time I could find no reputable breeders in the Bay Area. Otis came with a two-year health guarantee and microchipping, and I have nothing but good things to say about the breeder. Her name is Linda Bush of Bejaze Yorkies.
http://www.bejazeyorkies.com/
I also have a friend who purchased a Yorkie from Bejaze who's is totally in love with her dog, too!
Please let us know if there's anything else we can help you with.