then check out Malcolm Manning's Introductory essay.
To get the big picture, read Harvest: One History of Contact Improvisation written by Nancy Stark Smith, who was there in the beginning.
You also may enjoy Elizabeth Zimmer's great article from Dance Magazine.
Martin Keogh wrote an essay 101 Ways to Say No to Contact Improvisation: Boundaries and Trust that I consider one of the essential readings for anyone doing contact improvisation.
Karl Frost has a nice list of Fundamentals of Contact Improvisation.
Contact Quartery (often referred to as "CQ") is the "biannual journal of dance, improvisation, performance, and contemporary movement arts." It started out as a newsletter for contact improvisers to communicate with each other, and remains the main venue for this. It has wonderful articles and pictures, and in the back there are listings for contact improvisers around the world. You can order your own subscription of CQ on this webpage. If you are in Chicago, you can also get a copy through the Chicago contact improv jam, which orders a number of copies of each issue.
Contact Editions: "produces, publishes, distributes, and promotes non-periodical new dance literature." Here is where to find books on contact improvisation and a variety of subjects that many contact improvisers find interesting. Especially of note:
1. CQ/CI 25th Anniversary Sourcebook "Xeroxed articles, essays, drawings, photos, and quotes directly concerning Contact Improvisation, reprinted from Contact Quarterly, 1975 through 1992." This is by far my favorite resource. A rich collection of diverse ideas and views of contact improvisation - thought provoking, knowledgeable, and inspiring regardless of your skill level.VIDEODA: "archives, distributes, and produces videotapes of Contact Improvisation and other improvised dance and new dance forms." There is some great footage here. Especially of note: Fall After Newton "A sweeping look at 11 years of practice of Contact Improvisation by Nancy Stark Smith and initiator, Steve Paxton."2. Sharing the Dance: Contact Improvisation and American Culture by Cynthia Novack "An insightful look at the development of Contact Improvisation within its web of historical, social, and cultural contexts, written by an anthropologist and dancer." This book is often chosen as a text for university/college contact improvisation courses.
3. Taken by Surprise: A Dance Improvisation Reader. Ann Cooper Albright, David Gere (eds) "21 essays by prominent practitioners and scholars reflecting the development of improvisation as a compositional and performance mode. Including considerations of contact improvisation, recent innovations in tap dancing, and improvisation in everyday life."
4. Sensing, Feeling, and Action: The Experiential Anatomy of Body-Mind Centering® by Bonnie Bainbridge Cohen "Movement educator Bonnie Bainbridge Cohen describes her innovative approach to movement analysis and reeducation through her collected articles and interviews from Contact Quarterly, 1980-1992." Many contact improvisers find that the practice of Body-Mind Centering® creates new possibilities in their dancing.
PERFORMANCE & WORKSHOP/CONFERENCE PROJECT: "organizes symposia devoted to the investigation, dissemination, and performance of contemporary movement work. "