Yup...
Start with expedia.ca...It may not have the absolute cheapest flights, but it's comparable/competitive...it's a good starting point because it's so absolutely user friendly....I LOVE it! You get to pick non-stop/one stop/two stops, have control over the price range and choice of airline. Don't like that 7 am or 11 pm flight? Choose your departure and arrival times from a list of options!

I've booked with expedia more than once (and I'm not shilling) because of it's user friendliness...way better, imho, to any competitors I've seen, including travelocity and flight centre...