Stage 2: Finding a trustworthy breeder
Over several years some quality assurance schemes for dog breeders have started to operate. For pedigree dogs the most prominent is the Kennel Club's Assured Breeder Scheme. These schemes are aimed at raising breeders standards and are useful in doing so, but do not offer an absolute guarantee. Some are limited in scope or have standards that are not sufficiently policed. Many excellent breeders have adopted such schemes, but many also exist outside them. The Advisory Council has recently compiles a Standard for Dog Breeding which is a best practice guide that you may wish to refer to.
These are the questions you should ask about each breeder.