Will you be in Boston itself, or in the suburbs? There are several good shops in the area. International Bike, Back Bay Bike, Wheelworks (although, personally, I wouldn't send anyone there to buy a bike), CycleLoft. Let me know more specifically where you will be, and I can point you in the right direction.
SheFly
p.s.
This year's models may be mostly sold out, FYI. Manufacturers shorted their runs this year. It may be good to contact shops in advance to see what they have in stock.