This summer we rented an apartment in Montreal so I had easy access to McGill to finish up a program. We lucked out and found a place in walking distance to the Marche Jean Talon and the metro. A definite good find! If you have never been to Montreal, you may not heard of the Marche Jean Talon, which is an outdoor market where you can find EVERYTHING and it is a gf gold mine. Fresh veggies, meats, ethnic foods, etc.
Make sure to check out these places:
Creperie du Marche
I didn't eat here, as I had already eaten way to many sarrasin crepes in France last year. However they advertise their gf crepes! Just check about cross contamination before you eat here as they are making wheat crepes as well.
Saussicerie (sausage store)
many gf options here and delicious sausages! It is located at the back part of the market to the right about 5-6 stores of the bio store.