Book excerpt: If you're a fan of adventure and expedition stories, you'll know that most books in this genre focus on the expedition itself-the action, the struggles, the joys, the heartbreaks, the lessons, the rewards. But what about the events that happen prior to an expedition-the planning, the organizing, the logistics, the endless research, the pleas to prospective sponsors, the correspondence between team members? Most books in the adventure travel genre spend less than a chapter explaining "what came before." This book, however, is not like most. River Angels takes readers behind the scenes for a candid look at the simultaneous organization of three self-propelled expeditions and introduces the world to a burgeoning network of altruistic "river angels"-riverside citizens who not only assist long-distance paddlers, but also help preserve and promote the rivers they love.