Here is a few links to different mapping sites that might aid you in your area. Hope this helps.
Sanborn Maps(can be accessed at a library) very precise maps of each town. some dating back to the 1800's. This is my go to, to find maps for the towns I am searching.
North American Historic Maps and Atlases From Historic Map Works
USGS: Maps, Imagery, and Publications- this a large source that I have used in the past also.
Sanborn Maps(can be accessed at a library) very precise maps of each town. some dating back to the 1800's. This is my go to, to find maps for the towns I am searching. Some of the maps are listed with the Library of Congress and are HERE.(limited access)
Big Map Blog-I am new to this site. I was able to load and view maps from the early 1900's. Hopefully this site will help you.
Ghost Town Listings- This is another new site I am not that familiar with. In my immediate area there weren't any "maps" more of a "where was it" information.
Civilian Conservation Corp- This is a listing of most of the camps that were all over the US. Although there isn't a list for a "map" it still can help identify their location.
Menotomy Maps- What I saw of this site was good, but it is a work in progress. There are some maps and data available. A site to keep and eye on.
University of Texas Historical Maps- This is one of the sites that I got the info for the Dragoon story I wrote.
MAPPING SPECIFIC STATES
-as I get different State Info I will add it.
Montana lander owner data- I was able to search by landowner's name by county and found what specific plat was owned, location showed on a map.