Hmm, well...
Id find a building (perferable a castle) on a hill, and as said before id turn it into a fort. Barbed wire, bear traps, and plenty of guns/aamo. I would also keep a good storage of fuel in a tank, being that you could just steal it from a gas station.
In the fortress id have a small farming area, and a cold storage place for stuff that needs to be cool. (maby underground.)
Im pretty sure since we have acouple of military bases around here I might be able to get a armored vehicle. and if I cant do that id Take a pickup truck and put steel plates on the side, and wire on the windows.
IMO this castle posted by Turbografx would do good, or something similar. Being that there is water surrounding it. and only one enterance that I would keep closed/ pull up.