Banjoman,
Another on-line resource I used is Powell's Books (physically located in Portland, OR), where I found the following listing for you:
A folksinger's guide to chords and tunings. by Sliverman, Jerry Published by New York,Oak Publications[c1967] (0825600618, 1967) Section: Music-Sheet Music In Stock: 1 at $5.95 Trade paper; Used - Standard Condition; Location: Beaverton
The URL for Powell's is:
http://www.powells.portland.or.us/
Hope you can snag it!
Rose