For the Quebec form, you have to go to the Ministère du Revenu, the address is attached below. It's near to China Town, u can take metro to Place-des-Arts or Place-des-Arms (never remember the spelling of the station)
Direction régionale de Montréal-Centre
Complexe Desjardins
C. P. 3000, succursale Desjardins
Montréal (Québec) H5B 1A4