As we all know, saving the planet will require lots and lots of small decisions by each and everyone of us.   This handy celebrity-focused consumer guide provides a bunch of suggestions.  Use the power management tool on your PC.  Don't keep the water running in the bathroom sink while you're brushing your teeth.  Use bars of soap instead of liquid soap.  Stars and starlets abound, with a foreword co-written by actress Cameron Diaz and architect William McDonough, and host of handy tips from a cast that includes Martha Stewart, Faith Hill and Tim McGraw, and Owen Wilson.  As Wilson puts it: "I love this planet, and I love nature, and I love taking walks on the beach at sunset.   And if that makes me sound like Miss February filling out her turn-ons in a Playboy bio, so be it."