Vocal Method Books
There are plenty of different options here to choose from, and picking out the best ones is a matter of knowing where you stand now and deciding what your goals are for the future. For example, if you're a brand-new beginner looking for a versatile guide to general singing concepts and techniques, check out something like Alfred's Teach Yourself to Sing Book & Enhanced CD. This book covers a wide variety of styles from jazz to classical to musical theatre, and it comes bundled with a CD full of demonstrations and accompaniments to help you along the way.
Maybe you're looking for vocal method books not for yourself, but for your children? In that case, you'll be happy to hear that there are lots of materials dedicated to young singers. Have a look at the Hal Leonard Songs Children Can Sing! - Pro Vocal For Kids Vol. 1 (For Boys And Girls) Book/CD, for instance, or the Hal Leonard Essential Repertoire for The Young Choir Level One (1) Mixed/Student book. These vocal method books for kids are approachable enough for young voices, and the exercises they teach will help them develop into fantastic adult singing voices over time.
Any musician would tell you that playing an instrument is a rewarding experience, and singing is the only musical discipline that gives you the opportunity to actually be the instrument yourself. That makes it especially rewarding in its own special way, so if you've been thinking about taking up singing (or if you have a child at home with dreams of the stage), there's no better time than the present to pick up some vocal method books and get started. The results will speak (or is that sing?) for themselves!