Many people have already given you very good, sound advice. I personally would only buy from a breeder that I could meet locally, and ask all the questions that I wanted to . I just feel like it is too much of a risk to buy online, and not to see the puppy beforehand. Or the parents, and breeder.
Before getting my first Yorkie i did look at internet sites, and shipping. However, it was not for me . I got a pup that I could meet the breeder and drive to her house. I found out later though, that she had other puppies from other breeds
She lived out of the middle of know where, it made me mad to have found that out
She did tell me that it was her first litter of Yorkie pups.
It is very hard to find people who you can trust, and tell you right.