I just bought this book today at my local Obon festival. For those of you who don't speak/read Japanese, it's in English, and it provides basic how-to instructions on themed, seasonal and regular bentos, as well as recipes and techniques along with the time it takes to make the box. There is also a chapter on useful foods for the five colors mostly used in bento (brown/black, white, green, red and yellow.) There are even some "Americanized" recipes in there as well.
I am really happy with this purchase, and I hope those of you who follow my advice of buying it will be pleased with it as well.