Fumio Demura's basic books on Kobudo (I have Nunchaku, Bo, Sai, Tonfa) are good. They include some historical data, basic stances and grips, as well as useful drills to train grips, blocks and thrusts. This book on basic Nunchaku, however, does not present a Kata with the weapon, as the Bo book does. Some more on Japanese nomenclature would have been great, also. Still, I recommend it for beginners.
The pictures could not be easier to follow, the clarificatons and applications of each strike, swing, block or movement are nicely explained and demonstrated. Also the self defence application section is a great way to remain motivated. A beginners' form would be sweet to have. But its a great buy. And yes, I think you must have some martial art experience before you pick up this book.