Well it's not that non-touristy but the north side of Lake Thun in
Switzerland would be one of my recommendations, pick one of the villages away from all the Japanese tourists in Interlaken.
Coeur D'Alene, ID is also a nice place to visit, there is a
hotel there right on the lake which is a bit of a tourist trap but there are other places to stay.
I used to like Vero Beach, FL but I'm not sure what it's like now, haven't been for years.
Bangor, Northern
Ireland is quite a nice seaside town. There's quite a lot to do in Northern
Ireland actually but people generally don't think of it as a tourist destination.
Steve.