Hello Sheila,

I don't have any additional information to what you have provided in your post. If you haven't already, you might try to contact Doug Harger. Doug is the recommended expert on AA families in the west central counties of Ohio. Here is a posting from Doug Harger dated 2006 giving an example of his RICKMAN research. Your Abraham is probably Abner according to Doug's findings.
http://tinyurl.com/42o277s

You might also try www.familysearch.org and their updated Ohio records searching for any RICKMAN records in Darke and/or Mercer Counties in Ohio.

Sorry I can't be of more help,

Art Thomas