I am also researching the same families that you are: Domer, Harter, and Hartman.

My G-Great-grandfather was Moses Domer who married Phebe Hartman. I am also related to the Harters. My G-grandmother was Matilda Harter. All families lived in the Elkhart and surrounding areas of Indiana.

Since you seem to have far more information than I do, could you fill me in. If I have any information that will help you, I will be glad to assist. My G-Grandfather was Adam Domer, brother to Sarah Ellen Domer.