For example a Ragdoll is more likely to adapt living on a small apartment than a non-pedigree cat. Buying from a reputable breeder also insures that your kitten is healthy and it has been given the best possible start for its life. Unless you want to take your cat to a cat show or become a breeder, a pet-quality kitten is what you are looking for. Keep in mind that the price is going to be only a small part of the money you are going to have to spend on your cat for its lifetime, papers or not. Your country has at least one cat association for pedigree cats.
All reputable breeders register their kittens on at least one association.
Cat magazines and books have often contact numbers for these associations, which can at least contact you with Ragdoll clubs or the local cat association. They have a list of breeders and they can tell you where to find the nearests. You ll be able to see Ragdolls yourself and talk with their breeders and owners. Breed clubs also often publish their own magazines, which can be useful with care tips and breeder introductions. This page is also a good start to your search.