How can I access my money in Montr�al?

Your debit card should work in Canada. Perhaps not at every single machine, but at most of them. It gives you a very current exchange rate. It's not a bad idea to have some Canadian money before you arrive in Canada or very soon after. Many Canadian businesses will accept US money but the exchange rate they give you is usually not good. You should be able to exchange at your bank at home, but call ahead because not every US bank keeps Canadian money on hand and they might have to arrange to get it in for you.There are currency exchanges in many airports, and often at land border crossings.