There is one in Leominster, west on rt2 from Groton, called NFG Home Brew Supplies. Really only open a few hours during the week, but good grain prices and a really nice guy. http://www.nfghomebrew.com/
A couple of others, getting to be a distance from you though...
One that I used to go to is in west boylston, Home Brew Emporium
Another one a little further away is in Marlboro on rt 20. Strange Brew www.strangebrew.net
How are you coming home? from the south, north? There may be a few on your way that you could hit.
Beer Stores: There is a Kappy's in Leominster...nothing great, but an ok selection. Sorry I can't be much more help, I'm a little west of there.
EDIT: Just noticed you are coming from NY...