Soda, his song database (including chord sheets) is available free of charge and with John's blessing at http://www.chillywinds.com
There is a group of the most rabid fans in the world of John's called Bloodliners (after one of his best songs, California Bloodlines)
John was one of the most interesting people I've ever known. His "loudest folk band in america" was one of the greatest bands I've ever seen... I hitchhiked hundreds of miles to see them play... and the people who saw them would say the same thing.....