If you read the topic "How to Find a Good Breeder" and the cehcklist from the Humane Society, that should give you an idea how a responsible breeder operates. Bottom line is that a responsible breeder truly cares about the well being of her puppies and would never, ever let them go to a third party to be sold without having any say in where her they will end up. As far as the ad goes, of course, no one is going to advertise that they get their puppies from puppy mills, so I wouldn't believe anything claimed on that website.
Unfortunately, the fact that the broker's place was clean has nothing to do with the situation your puppy was born into. Most puppy mill puppies are raised like rabbits in cages stacked one on top of one another.
The best rule on buying a puppy is to visit the breeder before, see BOTH parents, get vet records for both parents (you want to make sure genetic screening was done before breeding) and get references from happy customers many years later.
While a puppy that you've only had a few months can seem heathly, happy and awesome, genetic problems often don't surface for years (epilepsy, for instance, usually doesn't begin until a dog is 1-5 years old).
Not only is it hearbreaking to have a dog with a chronic illness, it can be financially devastating. Not many people buy a puppy with the expectation that their medications alone will run upwards of $150 a month, as is the case with my Lady. Do the math - that's nearly $2,000 a year and doesn't include vet bills which have exceeded $1,000 for the past several years.