I don't think Amherst, MA is the sort of place where you would actually need to invest in seasonal tires. Just get a set of decent AT tires and you'll get around just dandy. My BFG ATs had me going last winter in a foot and a half of snow shuttling hospital staff around just fine, and I'm going to get over 65,000 miles out of 'em by the time they get replaced this fall.

Check around and find a shop that will give you some decent $ for your current tires, you ought to be able to fetch a couple hundred for 'em.

Brent