Yup, back country, free camping, overland camping...What do you mean by boondocking? Back country camping? NH and Maine will be your best bet. White Mountain National Forest in NH or almost any place in Maine.
Keep in mind, both Central and Northern NH/ME got hammered with snow this year. So most of the roads are closed for mud season. Please respect that. When people don’t, it ultimately leads to closed access.
Awesome!! I'll def check it out!A great app for finding free camping and good back country campsites is iOverlander. I know people who have used it all over the world with great success.