I have had Karate Katas of Wadoryu
by Shingo Ohgami since I started karate and it's probably the most useful book on Wado Ryu katas I've come across.
Whenever I was taught a kata at karate I would go home and practise it again and again. Occasionally I would forget a few moves and have to wait the rest of the week to find out what the moves I had forgotten were. This book meant that I could check the moves immediately.
There are a few books like this around, each with their advantages and disadvantages. I prefer this one as it tends to focus more on the application of various moves as well as giving a clear step by step guide with photographs to help you.
I would recommend this book to both students and instructors.
Karate Katas of Wadoryu
starts by defining what a kata is and showing how the katas relate to each other. It then moves on to discussing various stances giving their Japanese translations. Inner and outer blocks are then discussed.
Katas covered in this book are the five Pinan katas (Shodan, Nidan, Sandan, Yondan (Yodan) and Godan), Kushanku, Naifanchi (Naihanchi), Seishan and Chinto.) Before each kata there is a short introduction.
Each move is given half a page. There is a reasonably large photograph of Shingo Ohgami performing each move and a caption underneath explaining each move and giving the motivation behind it. Occasionally the application of a particular move is demonstrated on an opponent. I've found that this book often gives a different interpretation of a move to what I've been taught, but this just goes to show that different moves can have a a wide variety of applications.
One nice feature I've found is that after some of the katas there is an explanation of a section of Wado Ryu karate. Although only at most a few pages long these sections give valuable insight into Wado Ryu and really help you understand the style. Some topics covered are the general stances, the mathematics of a punch and energy curves.
Overall this book provides an illustration of the katas and an in depth discussion of each move as well as general articles on Wado Ryu. Do bear in mind that although this book is very useful, it's no substitute for a qualified instructor. I prefer learning the kata under instruction and then using the book to reinforce what I had learnt.
Another thing worth mentioning is that different clubs do have small variations in katas. These differences are usually minor, but anyone reading a kata book should bear this in mind.