As I thought, "high lonesome" is a southern folk expression. Here it is in a blues song by Lucious Curtis, recorded by Alan Lomax in 1940:

http://weeniecampbell.com/yabbse/index.php?topic=5109.0;wap2

Alan Lomax had an ear for poetic and evocative folk expressions and liked to highlight them in his writing and conversation. For example "my heart struck sorrow" -- a blues lyric that he he used as the title for a section of Land Where the Blues Began. He was actually sometimes taken to task for writing purple prose because of this habit! But he did it advisedly. He was a rebel who never would accept the castrated modern stripped- down adjectiveless writing style recommended by Strunk and White that has become journalistic orthodoxy.

Lomax was using "high lonesome" as a category of Cantometrics in a conversation recorded in 1965 with a Mexican scholar Americo Paredes. It is summarized and can be heard on the Culutral Equity website: http://research.culturalequity.org/get-dil-details.do?sessionId=33

Personally, it is my impression that the Appalachian manifestation of the ornamented "high lonesome" was retained there by the Old Regular Baptists in their lined-out hymns, and had been common in Scotland (perhaps also in 1600 England and Ireland). Ralph Stanley is an exemplar.