
as far as i know the sites admin check any complaints that they get about registered breeders but not sure (someone else will be a long soon to clarify)
just make sure that you are clear with them about what you want in your pup and your breeder- i'd suggest you take a list of questions to ask as we all forget ourselves with a gorgeous batch of puppies running about us.
look at the breeders adults, see if you like the look of them as there is still a lot of variation within breed. check if the sire and dam have both had (and passed) the appropriate health checks for the breed, see if you like mums temprement (you'll probably not meet dad but they should have a picture at least). make sure you get your papers with the pup. i think its prudent to ask what medical conditions have cropped up in the line before and morbid as it is perhaps what and when their other dogs of the line have gone to the bridge (does anyone else do this? it just strikes me that a dog often takes after its family and it gives you an idea of when to start looking out for things, i may be a loony though)
there are loads of other things but i can;t think of any now...