The best collections of Michigan maps are at the Michigan State Archives and at the Burton Historical Collection. The Family History Library has a small collection of maps and atlases, dating from 1855 to the present. The library's files include ward maps for the city of Detroit.
United States Census Bureau State and County Map. This map will allow you to zoom in on any state or county in the United States and read the names of all of the neighboring counties.
To locate Michigan maps and atlases, use:
Miles, William. Michigan Atlases and Plat Books: A Checklist, 1872–1973. Lansing, Michigan: State Library Service, 1975. (Family History Library book 977.4 E3m; fiche 6051141.)
Printable maps are also available from the National Atlas of the United States -- http://nationalatlas.gov/printable.html