The Law Bod has subscriptions to legal databases which are good for Canadian materials: for licensing reasons access is limited to current OU students & faculty members. Principal examples can be reached via links below.
Holders of an Oxford SSO can access Halsbury's Laws of Canada via LexisLibrary
and the Canadian Encyclopedic Digest ("a comprehensive statement of the law of Ontario and the four western provinces - provincial, federal and common law - as derived from the case law and legislation") via Westlaw UK (International Materials)
There are some reliable sources of Canadian law on the free web. CanLII is the most useful starting point for primary sources both federal and provincial.
Please check the other sections of this Libguide for other online resources & more detailed research guidance.