WHAT — "Pedometer Walking: Stepping Your Way to Health, Weight Loss, and Fitness" by Mark Fenton, David Bassett, Tracy Teare. Globe Pequot Press. 184 pages.

HOW MUCH — $13.

WHERE — Any bookstore or online.

WHY BUY IT — This book is a manual on how to use and understand your pedometer. It was first published in 2006, it's still in print, a testament to its reliability.