From Ancestry.com (random collection of useful Canadian links)
Census of Canada Collection
1900s 1901 1906 1911 1916
1800s 1851 1861 1871 1881 1891
Quebec Vital & Church Records (Drouin Collection)
Baptisms, marriage and burial records dating back to 1621. Best resource for French-Canadians.
Birth, Marriage & Death Records
Vital records provide rich details and form the backbone of your story.
Canadian Passenger Lists
Over 7 million names, 40 years and 4000 ships.