I've been studying Elizabeth Cotten's guitar style via John Miller's excellent DVD lessons. For each song on the DVD, they show you archival footage of Libba playing the song, then John plays it the "normal" way (i.e. right-handed playing, right-handed stringing).

It is weird to watch Libba's technique, but it sure sounds beautiful -- she had a wonderful sense of tone & melody as well as a graceful, smooth rhythm. Interesting that unlike other Piedmont fingerpickers as well as contemporaries like Mississippi John Hurt, Libba Cotten did *not* play swung eighth notes -- you do *not* hear that ragtime-y emphasis on the 2nd & 4th beats of the measure. Her playing style seems to owe more to the parlor guitar style of the late 19th century than it does to 20th century blues & ragtime.