Library and Archives Canada has a large collection of Canadian provincial and federal official publications, some of which include information of great interest to genealogists, for example, the Canada Gazette contains military citations, lists of new citizens, notifications of name changes, etc.
The Statutes of Canada, for certain years, include divorce acts. The Sessional Papers include a wealth of interesting material on many subjects including lists of civil servants, persons who made claims for losses in the rebellions, etc.
We also have strong collections of official publications for countries such as Great Britain, France and the United States.
Search for official publications in AMICUS.