I'm probably preaching to the choir in a story about guitars, but if you're looking for some good 12-string music, Leo Kottke's 6 and 12 String Guitar is a good start.

If you haven't heard (or seen) Michael Hedges play a harp guitar, there's some background and links to videos here:

https://michaelhedges.com/michael-hedges-the-harp-guitar/