I really enjoyed Mr. Webb's book, but it's not a scholarly work (I think it even say that in the preface). It's more of an extended essay. He uses a lot of sources, but they're almost always secondary, and sometimes even further removed.

I think the point of his book is to point out some of the history and heritage of the people of the Appalachians, which has been largely forgotten (not by historians, but by the people living there today).

Back to the original subject, I know a young fellow who recently completed a degree in archaeology with an emphasis in Celtic Iron Age. I kept asking his dad what you do with a degree like that. Turns out you go to graduate school. In England