Maps are a useful way to get a pictorial view of where your ancestors lived. There are various types of maps you can consult - ranging from the topographic maps that show contour lines, elevations, and place names to the thematic maps that show things like diocesan boundaries and areas.
The following web sites have maps of various sorts that you should find useful in your research. Wherever available, information on how to obtain these maps is given as well.
Using maps in genealogy
Using Maps in Family History Research, Lessons & Links (2003)
Global Heritage Press
Consult at: OGSL
Using maps in tracing your family history (1974)
Ottawa Branch, OGS, Ottawa
Consult at: Carleton University; Ottawa Branch, OGS
Geographical Townships in Carleton County
Historical maps and atlases
Concise historical atlas of Canada (1998)
edited by William G. Dean ... et al.
Selection of 67 plates from the Historical Atlas of Canada
Includes bibliographical references
Historical atlas of Canada : a thousand years of Canada's history in maps(2002)
Douglas & McIntyre, Vancouver
Includes bibliographical references and index
Where is here? : Canada's maps and the stories they tell (2002)
Penguin Books Canada, Toronto