i lookied up on ther sing out! web site and there is an index of all
songs published...but it went form Ode to a Gym Teacher to Oh, America.
no Oedipus. Here is Mark Graham and Orville Johnson's web page
http://www.mongrelfolk.com/ i am looking there now...
here is a quote from a review:
"Mark Graham's song "Oedipus Rex" is the Greek classic condensed and updated with a wry sense of humor. I was thrilled to discover this is their third record for Green Linnet."
on May 12 these three songs were played on a radio show...
# Mark Graham & Orville Johnson: Oedipus Rex Kings of Mongrel Folk no label (206-932-4971)

# Severn Darden: Oedipus The Sound of My Own Voice and Other Noises Mercury OCM 2202

# Tom Lehrer: Oedipus Rex The Remains of Tom Lehrer Rhino R2 79831

I think that would have been mother's day as all the songs mentioned
mothers.http://www.midnightspecial.org/chicago/c20010512.html