I have read those books too!
If you are interested in Japanese contemporary art, you might want to read the following books:
Superflat by Murakami. The book is older, so you've probably already seen most of the art, but the book explains his theory on the "Superflat" movement in Japanese contemporary art.
The Age of Micropop
catalog to the
Door Into Summer: Micropop where Midori Matsui explains her theory on the Japanese art she calls "Micropop".
The
catalog to the current Aida Makoto and Akira Yamaguchi show at the Ueno Royal Museum is interesting.
Also, if you like Aya Takano and her contemporaries, you might check out the
Tokyo Girls Bravo book.
One problem with these suggestions is that most of them are catalogs to Japanese art group shows, so maybe they are a little hard to find outside of Japan. I will think about other possible books and try to post more suggestions later.