The AKC classified list is questionable. Anyone who registers with AKC can list there. AKC registration is important since it is the only valid registry in the US but the value of the registration is only as good as the breeder. A dishonest breeder can easily switch litter registration slips around along with the names of the parents.
Other than a YTCA breeder the next thing to check is your local breed or conformation clubs. AKC sanctions clubs that put on shows through out the country. These clubs usually have a breeder referral contact person that can point you in the right direction for the breed you are looking for. Try searching for a club in your area. There should be several where you are located.
American Kennel Club - Club Search and Directory
Most clubs are all breed conformation clubs that include many breeds but there are also some specialty clubs for the various breeds. Do a search for both in your state or a nearby state.
Most of these breeders will sell pups as pets for less than their breeder or show quality pups. You are more likely to get a pup that is in good health and a good representative of the breed this way. Always check out the breeder though. Every kind of industry in the world has their bad apples and show breeders are no exception. Get references and go to the place if at all possible. Go to a show if you get a chance. They are fun to watch and you can learn a lot.
There are many good looking scams on the internet. Stay way. When you do a search for a Yorkie pup online a lot of fancy sites will come up. Beware. Most are puppy mills or brokers in disguise. If they are trying to sell you a "teacup" or very small puppy, run away. The Yorkshire Terrier is not supposed to be over 7lbs. It is already a very small dog. People trying to produce tiny dogs totally disregard all established guidelines for the breeding of purebred dogs. Many of their "teacups" end up being over size. They are creating terrible health problems and genetic defects in the dogs. People have found there is big money to be made by selling small breeds puppies. They are out there by the thousands.
A puppy does not develop the ability to hold back urine until it is about 16 weeks old and that is just the start. If someone is trying to sell you an 8 week old puppy they are selling you an infant that is very needy and is not going to be potty trained for a very long time. Most good breeders will not sell their pups until the are at least 12 weeks old. Some will hold them longer if the puppy is not really ready to leave yet. You cannot accurately evaluate the quality of a puppy at a very young age. If a person is just breeding for the money they will want the pups out of there as soon as they are weaned because that is when the mom stops cleaning up after them.
Most show/breeders will sell you a puppy for between $1200 to $1500. A lot goes into breeding healthy good quality puppies. You can get a puppy from a backyard breeder or puppy mill/broker for less but you are taking your chances with the health and quality of the pup. Some puppy mills or brokers as well as BYB's will charge up to $3000 for a very poor quality puppy that they claim will be very small. A good breeder would only charge that much money for a really good show quality pup. Most of us just want a healthy pup but that is not what these people are breeding.
Take your time in finding the right breeder. Your puppy should be a family member for 15 years or longer.