Universal Placebos gathers news, research, and musings about placebos, and even offers some for sale.
Another good, rich source, of course is Dan Ariely’s Predictably Irrational — both the book and the associated ever-growing web site. Both include accounts of Ariely’s Ig Nobel Prize-winning research, which demonsrated that high-priced fake medicine is more effective than low-priced fake medicine.