his page indicates how to install / use Debian in your local language.

See :

Zones and countries

*user-de package for german users. http://www.debian.org/doc/manuals/debian-euro-support/debian-euro-support.txt

**http://packages.debian.org/unstable/misc/user-ja.html **http://penguinppc.org/~hollis/linux/nihongo.shtml