Bring a digital camera, take pictures, and notes. Ask a lot of questions, pretend to be interested, ask about meeting the puppies' parents, etc. Theater - on the first visit, act act act so they don't get suspicious. If we're lucky, they are rescue pups brought in from somewhere, but I admit that's unlikely, given your proximity to Pennsylvania. And once you get some facts under your belt, contact the local media, get a news or TV crew in there, and then if necessary, find where you can legally picket them! People need to know!