There's a dyno less than a mile from my place in NH if you can't find one in ME. He's fairly reputable although he sort of tweaked out my tune...but come to find out, his wideband was malfunctioning. Since his readings were more rich than my AEM, he used his to stay on the "safe" side. Prices are fair and he offered to fix me up. I however will be trekking to CT for my next tune! If you want more info hit me up, he tunes ALL the subarus in my area. From Maine taking 101 to 93, he'd be exit 4 off 93.
EDIT: I googled "dyno tune MAINE"
http://www.google.com/search?q=DYNO+tune+Maine&ie=UTF-8&oe=UTF-8&hl=en&client=safari
I don't know if any of those spots are near you but I first googled "dyno tune near Freeport, Maine" with no results.