I would.
get to know the breeder, talk on the phone, email. etc.. you will get a good idea of WHO They are. Its usually pretty easy to find someone who has a puppy from the breeder, talk to them about their experience
are they concerned of your home environment? Do they have an applcation? Do they ask you a lot of questions? Do they mind you asking questions? those are all good signs

a VERY important thing in my opinion is, will they take the dog back for ANY REASON at ANY TIME if you can't keep it? that shows that they truly care for the dogs they are producing
a website can also be very telling but it also can be VERY tricky. its easy to write down all the right things.. So I would make sure to call if it was me..its a lot harder to lie/answer questions untruthfully over the phone on the spot then when typiing out an email
as stated above, watch out for breeders with WAY too many people, no pictures of parents, no health testing, contracts, and "pay and get your dog" kind of things.