i just graduated from amherst college, i was gonna try to go to these shows but since i don't have any money i don't have me any phish. i saw them this summer though and they killed it. shouldn't be too hard to find some nice woods to set up your tent. damn, reading all this is making me miss school...
if you're in amherst town itself you should hit up Antonio's for pizza, otherwise down by UMass campus, like people said, the Hangar is great. On Mondays and Tuesdays, 4-6 PM it's $8 all-you-can-eat wings and $5 pitchers.
also in town is Bueno Y Sano, good mexican and it's $5 large burritos on Tuesdays. and Veracruzana for more cheap but delicious Mexican. and i know you want to have a traditional West African meal while you're there... Baku's get a plate of rice, plaintains and goat meat for like $7
other places can get a little more expensive.
great weed out there too.