Both a Japanese and English version exist, and it seems like there is much more listed on the Japanese version, but the English one is okay.
It is a '˜bear club' in case you didn't get it, and while the English is a bit stilted, its understandable. Some covers of a bear magazine are shown, plus there are some links.
Not really a whole lot, but hey, few minutes of time isn't a huge loss. They do have a downtown Tokyo office, where if you traveling there, you can get help in English. So worth making a note.