Minnesotan here! I find much of the material in
Sepp Holzer's Permaculture and
The Resilient Farm and Homestead to be very useful, even taking into account that my
land is flat, lower altitude, and just a notch colder than theirs. I'm curious about the book
Farming the Woods, though I don't have much mature forest to work with. Might be just the thing for you!
In internet searches, I always make sure to use the term "cold climate", and keep seeing the same list of candidates: apples, nuts, blueberries, cranberries, seaberries,
honey berries,
mushrooms. I'm hoping to incorporate all of them eventually.
Eagerly awaiting further advice on this!