Sounds fishy to me -- you don't "sell" papers if you take breeding dogs as seriously as you should, so you were dealing with a back yard breeder. My guess is, based on that, that even if you got the papers, they wouldn't prove much.
The only use really of a pedigree is to tell you the family history of the dog -- if you don't know who the dogs are, it's pretty meaningless, because there's not likely to be anybody who knew the dogs personally, had seen them up close and personal, and could tell you about them.
If you're really curious, you can call the breeder and ask for the pedigree/registration name and number of the mother of the puppies. Surely she will have THAT much (unless she has an excuse for that, too). If she doesn't have THAT, then you really are dealing with somebody not on the level, in which case continue to love him as a beloved member of the family and be sure to neuter him and his sister ASAP.
You didn't mention wanting to breed, but without knowing the family background for health reasons, you should never breed any animal (and most of the time even if you DO know the family background you shouldn't either! There are many, many Champion dogs out there that have no business being bred for one reason or another. )
If you're interested in registration for the purposes of competing in AKC performance events (agility, obedience, etc.), you can apply for an ILP number which is a sort of registration number given to neutered dogs that appear purebred. You'll have to do some paperwork and submit some photos, etc., so unless you plan on competing it may not be worth your while.