Please don't bowl straight into a fully working or trial bred Golden without considering what they're bred for. A trial bred dog is not, IMO best suited to a life a a family pet. They are highly intellegent, highly strung and in need of a mammoth amount of stimulation to keep them happy. A blend of a show and working bred dog would be marvellous - both bright and beautiful!
I recommend you have a look on champdogs which does at least try hard to ensure their breeders are good ones - and they actively try to ensure they do not deal with commercial breeders or puppy farms. Of course there are also some bad breeders there, so look very carefully.
I recommend you contact the breed society in your area as a starting point and ask about litters. They will have litters registered from people who are ACTIVE in the breed which is a good start. Ask the contact if there are any litters they recommend and why.
Visit the puppies. Make sure you see Mum at the very least - google the name of the sire and see what you come up with. Learn the meaning of FTCH - field trial champion, FTW - field trial winner, SWCH - show champion etc so you are a bit more aware of what you're dealing with. The parents must be hip and elbow scored and the certificates available to view. They must also have an eye test certificate which is only valid for 12 months. Do not accept any excuse for these things not being present.
Ask to see the dam and sire pedigree certificates and note their pedigree names, and their grandparents names. Go home and google them. See if anything comes up.
I would also visit the Kennel Club website to verify the health certificates are valid.
Make sure the puppies are in a clean and cared for environment. That they're in a house with noise and life all around them, that the breeder is socialising them well - that the get to play outside for example from about 6 weeks onwards.
And if you have any doubts, ask on here. There is a great deal of knowledge here which is happily shared.