The American Medical Association's Council on Ethical and Judicial Affairs (CEJA) publishes a Code of Medical Ethics, comprised of CEJA Opinions, CEJA Reports, the Principals of Medical Ethics, the Fundamental Elements of the Patient-Physician Relationship. Some of this material is available through the AMA Code of Professional Ethics page. The Code is included in the AMA's Policy Finder, or you can purchase an print copy with annotations from the AMA Bookstore. For questions about AMA ethics, call the General Counsel's office at the AMA headquarters in Chicago (312-464-5448).
For more information, questions, etc., try calling the Institute of Medicine of the National Academies (202-334-2352), one of its regional libraries and/or another medical library or association. Look in the Encyclopedia of Associations (the three-volume hard cover, Lexis (BUSREF;ENASSC) or Dialog File 114) to find relevant associations and their telephone numbers.