The Guitar Songbook:

The VH1 DVD (Inside)Out:Warren Zevon featuring the making of The Wind and WZ's last hurrah:
(Obviously the cover was printed prior to the Grammy® Awards, as The Wind did win two.)

The Oral History Biography by Crystal Zevon:

And HERE is the link to Amazon's Warren Zevon.

"Everything is an Afterthought" - Biography of Paul Nelson, writer of the 1981 Rolling Stone article on WZ, by Kevin Avery:

"Lawyers, Guns and Photos" by George Gruel, Aide-de-Camp

See for purchasing information

There were two other songbooks: "Excitable Boy" and "Bad Luck Streak In Dancing School," long out of print, but infrequently available for exorbitant bids on eBay.

Here's a new book, as of June 2016...