With regards to getting tunes from Nathan's book, I've used a fair number of things there to augment my playing. However, Emmett was also a fiddler, and I get a dose of altititude sickness when I look at some of those arrangements. I'm always willing to try things out, but some of those arrangements are just plain high.
One thing I really like about Emmett's manuscripts however is that he has some very interesting introductions and endings, and I like trying to work these into some of the songs I sing. It'll nebber do to gib it up so is a good example.