Soon the tentacles of the BALCO doping case had reached into professional baseball and football, into Olympic track and field, into championship boxing, into the very consciousness of the American sports fan. There was grand-jury testimony and U.S. Anti-Doping Agency sanctions and congressional hearings with pumped-up athletes stuffed into designer suits talking about designer steroids. And now the trail has led to a three-story beige building in the cornfields of central Illinois, to a nutritional supplement company called Proviant Technologies and what investigators believe is the true genius behind the whole operation. To a 39-year-old organic chemist who signed off...