I am also researching John Jackson Allen with very little luck. However, during a recent web search, I turned up fragments of a member story on footnote.com. WHen I click the link, I get a general article listing. When I search the site, the article doesn't turn up. In any case, the text fragments from the search are:

John Jackson Allen and the CIVIL WAR …John Jackson Allen was born in Covington, Newton County Georgia on December 4, 1822. When John J. was seventeen his father, Mother, and sister died of ...

Quite interesting. If I can find the article or even the author, we may have found a good source.

I hope you have had some success since your post in 2003.

Fred Stevens