I just finished True Adventures with the King of Bluegrass: Jimmy Martin by Tom Piazza.

This is a very short book, essentially a reprint of a magazine article from Oxford American with an introduction and some essays added at the end.

But for all it's brevity, it is a must have for Jimmy Martin fans.  Martin has a reputation as being a trouble maker, and this book has some great examples from a trip the author and Jimmy made to the Grand Ole Opry.  Jimmy starts out drunk, berates Ricky Skaggs, and nearly fights another musician.  At the same time, he exchanges warm greetings with many others.