Don't think you can change $$ at the border proper, but your bank card should work in any Canadian ATM, depending on whether your local bank is on the PLUS or Cirrus system. Many Canadian ATM's are now compatable with both systems. It's probably your most economical way of changing $$.

The other bonus is that in many tourist areas, they will accept American dollars and give you (close to) the going exchange rate.

Enjoy Quebec...

Regards, John Hamilton, ON, CANADA