Over the weekend I bought the book "Electric Eden" for my e-reader. I'm not finished, but have made a major dent in it.
It deals with the British folk revival beginning with the early collectors (Cecil Sharpe, Ralph Vaughan Williams, etc.) through to the summit in the 60s and 70s when Fairport Convention, Pentangle and others were at their heights.
It is a large and dense read, but I think it has much to recommend it to the bard because of the way the author reexamines the nature of "folk" and "folk song" and the many ways they have played a role in British culture with many acknowledgements of paganism and nature in the genre.
People looking for inspiration may find that some of the artists mentioned, such as Vashti Bunyan or Nick Drake, will open doors for them.