Some of my favorite books that have really helped me put families together and find answers to my questions are local US county history books. These books could even help with your “Brick Wall Ancestors.”
The page below is from The Heritage of Geneva County Alabama, published in 2003. This book was published by the Heritage Geneva County book committee. They reached out to current county residents, past county residents and those with roots in the county to submit genealogical information on their ancestors and descendants.
My direct ancestor is Hugh C Davis. This article tells a little about him, but shares more about his brother which is information I did not have.
I have found these Heritage books in several different counties. One ancestors surname was originally “Lord” but the book told how they had changed their name to “Lloyd.” This was crucial information to be able to follow their descendants.
You can find these books on FamilySearch.org by using the Place Name search. Below is a short video to show you how to do this.
Find an ancestor in your family tree who lived in the US and see if you can find a county history book!!