If you want to get a Russian Blue kitten, you should find out where, in your area, a good breeder is located.  Some people ask a local veterinarian or two if they know of any reputable breeders or of any family whose Russian Blue cat is having kittens.  Some Pet Clinics will let you advertise for a pet on their bulletin board in the lobby of their office.  You want a healthy pet that came from a mother who was not over bred by someone who uses their adult cat as a business.  Just like the puppy market, kittens too are not usually healthy when they are obtained from a source that is trying to make money, or a pet shop that gets their pets from places that are not licensed and regulated.  If you look on craigslist or one of those places in your area, let the pet owner know that the sale depends on a veterinarian health check up and don’t pay full price until you know that you are getting a pet that you will love for a very long time.