Resources

1. Historic Map Works -- the subtitle is residential genealogy.  I have only searched two surnames and one residence and I like what I see.
2. Sanborn Fire Insurance Maps -- I used this when researching my Vidunas clan in Pennsylvania.  I could really see how close they lived to the mines, the new school built of bricks and that they were within walking distance of their church.
3. Gjenvick Passenger Lists of Ellis Island -- I found my Vidunas immigrants using this site
4. The Map search of land ownership from the Library of Congress.  It can be a bit tricky to use, but you can search by state then by county.  Once you get the "slideshow" up, typically you have to click on the words on the slide from which you can find and search for your desired county.
5. A place to purchase maps.  You can download a small resolution map for 5$, or a printable version for 20$.  I don't know about you, but that seems very expensive.  Especially when your purchased item comes with their watermark all over it.  What I did was I found the map here on their searchable engine, then I went to the Library of Congress site (above) to pinpoint the map I wanted.
6. Some other websites I've not been able to fully explore but plan to include
1. Farm Ownership guide from Archives.gov
2. The Plat Plotter app which is supposed to work as an overlay with Google maps.  Should be useful when searching for present day locations for historical places
3. Students of Descent either have their own app or they list other ways of finding genealogically significant locations
4. Google Earth Hacks sounds cool, doesn't it?
5. Searching for Townships.  Need to try this one out
6. Heaven for Genealogists.  Well, I could use a little Heaven about now
7. A YouTube video I thought was important enough to include here
8. Another YouTube video I thought was important