A Summer Series post.
William Stringfellow published a lot of books.
Most of them are out of print, though a few have been reissued recently by Wipf and Stock, bless their hearts.
Fortunately, there is a fine one-volume paperback anthology of selected works, which went out of print fast but is now on the market again, at least the last time I checked, which was last year. It's a great place to start reading Stringfellow and covers the major periods and preoccupations of his life.
William Stringfellow, A Keeper of the Word: Selected Writings of William Stringfellow, edited by Bill Wylie Kellermann (Grand Rapids, Mich.: Eerdmans, 1994).