Roughly half of our direct ancestors were women. Most research hits a major snag when all we know is the name they went by after their marriage. You cannot move on with your research on this particular ancestor until you discover her maiden name.
One record that might help you find information is the widow's application records from military records. To qualify for bounty land and pension, she had to prove she was the wife of the Veteran. The affidavit is where you will find the most valuable information. In it, your ancestor could state, "I married William Smith on 29 January 1804, and before marriage, my name was Jane Doe." This information is straight from your ancestor.
Your most valuable records for finding information other than pension records are:
Family Sources
Civil Marriage Records
Religious Records
Children's Vital Records
Death Records
Cemetery Sources
Census Records
Newspaper Clippings
Court Records
Deeds
Please contact me at geneal@laurel.lib.ms.us if you need assistance with your genealogy research. You may also call 601-428-4313, ext 111, and leave a message.