Maine Airports
I live and fly in Maine, I would suggest a stop in Portland (PWM) and take a courtesy car into the Old Port section of Portland. There you can find many good restaurants, bars, shops and take a ferry boat out to one of the islands. Once you leave Portland, fly along the coast, stop in Rockland (RKD) for a look at the Owls Head Transportation museum (great old aeroplanes). If you continue up along the coast (or Downeast as we Mainers like to call it). You will come across Bar Harbor (BHB) The big island next to the airport is Mt Desert Island (Acadia National park). You can take a free shuttle bus from the airline terminal 5 minutes after the every hour and they will take you all over the island, into the park and just about everywhere else you might need to go. (plus it's free). There are a million places to get lobster in Bar Harbor, the Trenton Lobster Pound (right next to the airport before you cross onto the island is a great lobster shack).Make sure you view Acadia from the top of Cadillac Mtn before you leave (highest point on the Eastern seaboard).
Some other airports of interest in Maine
Eastport: (EPM) not too much there but you will be about as east as you can get in the USA.
Bangor: (BGR) (hee hee, just kidding)
Old Town: (OLD) say hi to Tina for me
Millinocket: Mt Katahdin, good for hiking
Pittsfield: (2B7) Home of Central Maine Skydiving (friendly, safe dropzone)
Belfast

BST) not too much here
Waterville: (WVL) Nice airport, nothing there.....
Greenville: Home of the International Greenville Seaplane fly-in (yeah!) 1st weekend of September
Frenchville: About as far North as you can go in Maine
Augusta

AUG) State capital (take a tour of the capital).
Twitchells: Great small family run airport with one of the few places still renting seaplanes (after a checkout).
Auburn/Lewiston

LEW) Hmmm, maybe a fly over would be a better choice.
Sanford

SFM) Right next door to Kennebunkport, home to Sr. President Bush (don't get shot down if you decide to do a buzz job) P67 on the sectional for the restrictions. Great restaurant Cockpit cafe (on the field)
Wiscasset: Scare the neighboors and do some low passes over the (closed) Nuclear Power plant right next to the runway.
Fryeburg: (gateway to the White Mtns of New Hampshire)
Biddeford: It's your standard Industrial Park airport, Old Orchard Beach is close by and you can watch all the fat Canadian Men strut around in Speedos. Gotta have Pier fries from Lisa's Pizza.
LittleBrook Airpark: Fun place to do some aerobatic flying.
That's most of the airports that I have been to in Maine
Goodluck!