New cousins, but no way to contact them

I’m trying to find out a little more about my Brown line this week.  I’ve traced back to my second great grandfather James M. Brown (b. circa 1853, Bloomington, Indiana).  I can’t quite get much farther back yet except that the 1880 U.S. census says his parents were both born in South Carolina.  I found a potential lead on more information in the Ancestral File database on FamilySearch, but I have no way to contact the contributors.  Aaaarrrrgggghhh!