Directories of heads of households have been published for major cities in Maryland. For example, the Family History Library has the following Baltimore directories:
|1752, 1796-1860||Family History Library fiche 6043563-601|
|1863-1930||Family History Library films 1376528-56 & 1605845-71|
|1914||Family History Library film 1697549 item 1|
|1940, 1956||Family History Library book Q 975.271/B1 E4p|
The Enoch Pratt Free Library at http://www.prattlibrary.org/, the Maryland Historical Society at http://www.mdhs.org/, and the Maryland State Archives http://www.msa.md.gov/ have large collections of Maryland city directories. Local public libraries and county and city historical and genealogical societies are another good source of city directories, especially for small towns and cities.
Find directories in the Locality Search of the Family History Library Catalog under MARYLAND, [COUNTY], [TOWN] - DIRECTORIES.