That really depends on transportation networks through the city and land values around the city.
Speaking of Edmonton, it actually has quite a bit of sprawl. Calgary has an enormous amount of sprawl. That's because land values around the city aren't extremely high yet, so developers can produce suburbs for relatively cheap (although they are getting really expensive). Plus alot of cities transportation networks is very car oriented, which is usually essential in suburban sprawl. So in cities like Edmonton and Calgary this can lead to smaller downtown cores and whatnot.
But compare that to the greater Vancouver area, or Montreal or Toronto, those cities have a more built up environment and huge downtowns becuase of population and limited ability to produce the sprawled out suburbs of Calgary or Edmonton. Vancouver, for example, it would be very hard to sprawl out too much because it's blocked in by rivers, mountains and other difficult geographies for construction.
This is comparable to US cities, but I've found that US cities usually have more sprawl. This is because of the Interstate Highway system and immense amounts of infrastructure for vehicles. Canada doesn't have nearly as much transport infrastructure, especially on a national networking scale. We only have one highway that goes from coast to coast... not nearly as many freeway type transportation systems. Notice in Canada too, usually the downtown cores are distanced from major freeway traffic (there are exceptions).. in the US most cities downtown cores have freeways running through or other major transport linkages.
So to directly answer yoru question, I would say, yes, CAnada is suburbanized, but not as much as the US is. Transportation routes are the main reason for this, but land values and city geography also play very important roles in this explanation. After studying this subject for some time it appears as though the US Interstate system is one of the biggest reasons for this disparity, as well as land use zoning in the US that isn't as stringent as Canadian zoning. This is becuase property rights in Canada ultimatley rest with the crown, whereas in the US it ultimatley rests with the individual. In both countries there is power at the government level to regulate or change land uses, but it's more difficult to do so in the US than Canada.
In the US, as well as Canada, there are many different city forms. Some cities, like Atlanta for example, are very sprawled out... others not nearly as much. My favourite city (in terms of planning, rejuvenation, and land use) is Portland, Oregon. They seem to balance car traffic with transit and pedestrian very well, and suburbanization isn't accelerated there becuase of the easy access to downtown and the desirability of remaining downtown.