Unbeknownst to your busy editor prior to all this in-gathering, the wonder-cabinet-analog Fortean Times has a link to a Melungeon-related article in the Morristown, Tennessee Citizen-Tribune up in its current online edition.
How Fortean.
Though it's mostly about "Big Haley" Mullins, and mostly about her obesity.
Mattie Ruth Johnson, below, is related to Big Haley on both sides of her family. I'd guess her coverage of this legendary moonshiner would be more interesting.
A picture on that last link above shows Ms. Mullins to have been a large, stern-looking woman.
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Wired also had some articles that were somewhat helpful.