My rubber band and ring routine "Ringleader" is in my new book Try the Impossible
, p.269, and as Ralph mentions, I have a video performance of it on my website at www.simonaronson.com
(on the New Book page).
My routine credits Bill Kalush's routine (the "original"), Michael Ammar's "Ring Band-It" (first printed in The Magical Arts Journal, Vol 1, #1 Aug '86, and later in The Magic of Michael Ammar, 1991, p. 135) and Dan Harlan's "Another Ringer" (A1 Multi-Media videotape, The Band-Shark, 1993). All three of those sources have strong elements and are worth consulting.
John Rogers includes his own routine in his recent lecture notes, and Tim Ellis (of Australia, currently doing a lecture tour here in the States) has a fine 3-phase routine (part of which I believe is based on Barry Govan's version).
Hope this helps.