Did you self publish?
I am in the process of doing the same thing, and was curious about the best way to proceed.
(I don't write about manga though...)
Although I have published my own stuff in the past, this book is not self-published. The publisher is Collins & Brown, an imprint of UK multimedia giant Chrysalis. Thanks to their marketing power, the book is available worldwide (in French as well as in English). You can order it online or buy it at your local book shop.
Good luck and have fun with your self-publishing project! It's a worthwhile pursuit.