The latest issue of Wired has not only a great piece on the history of Google Adwords but one of best explanations of the bidding process I have seen.
Really a "can't miss" article if you are interested in Adwords.
All about Search Engine Optimization (SEO), Pay-Per-Click (PPC) and web marketing for therapists, counselor, psychologists in private practice. Written by Peter Hannah, therapist and web consultant. Get clicks, and get clients!