I learned in Canada Census Indexes at FamilySearch Record Search that the FamilySearch Record Search index is pretty useless (it has all the people with the indexed information, provides reference numbers, but doesn't provide the parents, spouse or children in a family) and that there are no images available yet. I learned in Canadian Census Records that there is a transcription of the 1851 census at http://www.automatedgenealogy.com/ and that the images are available at the Canadian Genealogy Centre.
I am looking for my great-great-grandmother, Mary Jane Sovereen, born in 1840 in Norfolk County, Ontario, daughter of Alexander and Eliza (Putman) Sovereen. I went to the Automated Genealogy web site and clicked on the 1852 link up in the left hand corner of the page. The 1852 Province of Canada (Quebec and Ontario) page opened:
I put "Sovereen" in the Surname field and clicked on "Search." There were 42 matches - see the two screens below: