That John Burke book looks very interesting. I'm someone who believes that actually you CAN judge a book by it's cover (well, sometimes):
http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=1344172301&searchurl=an%3Djohn%2Bburke%26bt.x%3D0%26bt.y%3D0%26kn%3Dbanjo%26sortby%3D3

Unfortunately, it's long out of print and sells for quite a lot of money.

I think I'll check out some of Tony Trishka's books. They look interesting.