First State Coin and Sports Cards is a B&M store on Forrest Ave (Route 8) in Dover, DE. I have had a fair number of dealings with them and always recommend them when someone asks for a brick-and-mortar store in this area.
There was a small coin shop on Washington Street in Mt. Holly, NJ. It was there for many, many years. I actually used to work at the Crossroads Runaway Shelter which is right next door/above them back in the mid 1980's. I think the ownership changed hands in early 2000's, though. I met the new owner and he was very young and seemed more interested in getting sports cards and memorabilia for sale, so I don't know if they even still sell coins.
There are a couple small-time coin dealers in the Berlin Mart in Berlin, NJ. They mostly deal in modern coins and I felt that their prices were high the last time I looked there, which was probably around 5 or so years ago.
During the warm months, you can often find coin dealers setting up outside at the marts/flea markets. There was a really good guy at the Route 70 flea market. He had great prices, was very honest, and was set up there every week back when I was going there in the mid 2000's.
I think it's always a good idea to check outside vendors. Last I knew, the Pennsauken flea market was setting up at the old drive-in up in the Palmyra area on Rt. 73.
Hope this gives you a starting place.
