if you get near Freeport - home of LL Bean, definitely stop at the Haraseeket Lobster House - BYOB and the BEST lobsters and onion rings you will have, ever! get there early or later for the lunch crowd, it is amazing!
Harraseeket Lunch and Lobster Company | Lunch counter and lobster pound | South Freeport Maine Harbor
If near New Castle NH - a little difficult to find - try BG's Boat House - awesome lobster rolls!
Picturesque road is Route 124 off of Route 1 near Brunswick - this goes down into Orr's and Bailey's Islands - absolutely beautiful - obey the speed limits! check it out and hit the Cundy's Harbor Lobster Pound - great!
have fun and please report back!