When using images (and maps), you need to be very aware of copyright. Read the Copyright Basics circular from the U.S. Copyright Office in detail to start!
Many times, the documentation from a particular architect's office has been lost or is maintained internally or by the family. Sometimes it will make its way into a library collection.
If you're searching Google, try something like "architectural drawings collection site:.edu" to pick up archival collections at various universities.
Use these to search the library catalog more efficiently and effectively - enter them in the "Subject beginning with" drop-down in the UMD catalog or the "Subject" field of the advanced search in any library catalog.
Try some of these for images and maps:
Photographs --Catalogs
Photographs -- [any geographic location]
[any geographic location] -- Pictorial works
[any geographic location] -- Maps
Although many of these photographs remain under copyright, the "photo morgues" of newspapers and magazine sometimes make their way into libraries and can be a great resource. Some are online, and some are close by!
UMD's map collections are in three locations: Hornbake Library/Maryland Room (Maryland maps), McKeldin Library 4th floor (government maps) and online (databases).
Pre-Internet, people laboriously created lists of what maps appeared in what books...they're still helpful! So are online bibliographies.