There are lots of fonts for Japanese:
Code:
$ apt-cache search font | grep Japanese
dvi2ps-fontdata-three - Font data of Adobe Japanese fonts (futomin, futogo, jun101)
fonts-aoyagi-kouzan-t - Brush-style Japanese font
fonts-aoyagi-soseki - Brush-style Japanese font, Aoyagi-Soseki
fonts-dejima-mincho - antique-looking Japanese TrueType Mincho font
fonts-hanazono - Japanese TrueType mincho font by KAGE system and FontForge
fonts-horai-umefont - Japanese TrueType font, Ume-font
fonts-ipaexfont - Japanese OpenType font, all IPAex Fonts
fonts-ipaexfont-gothic - Japanese OpenType font, IPAex Gothic Font
fonts-ipaexfont-mincho - Japanese OpenType font, IPAex Mincho Font
fonts-ipafont - Japanese OpenType font set, all IPA Fonts
fonts-ipafont-gothic - Japanese OpenType font set, IPA Gothic and IPA P Gothic Fonts
fonts-ipafont-mincho - Japanese OpenType font set, IPA Mincho and IPA P Mincho Fonts
fonts-ipamj-mincho - Japanese OpenType font, IPAmj Mincho Font
fonts-kiloji - Japanese Truetype font like longhand made by "kilo"
fonts-kouzan-mouhitsu - Brush-style Japanese font, Kouzan-Mouhitsu
fonts-migmix - High quality Japanese font based on M+ fonts and IPA fonts
fonts-misaki - Japanese Gothic and Mincho font from "Misaki" bitmap font
fonts-mona - Japanese TrueType font for 2ch ASCII art
fonts-monapo - Japanese TrueType font, Monapo
fonts-motoya-l-cedar - Japanese Truetype font, Motoya L Cedar
fonts-motoya-l-maruberi - Japanese Truetype font, Motoya L Maruberi
fonts-oradano-mincho-gsrr - Retro style (Meiji period) Japanese font
fonts-sawarabi-gothic - gothic font for Japanese
fonts-sawarabi-mincho - Japanese mincho font - Sawarabi Mincho font
fonts-seto - handwriting Japanese font including JIS X 0213 kanji
fonts-takao - Japanese TrueType font set, Takao Fonts
fonts-takao-gothic - Japanese TrueType font set, Takao Gothic Fonts
fonts-takao-mincho - Japanese TrueType font set, Takao Mincho Fonts
fonts-takao-pgothic - Japanese TrueType font set, Takao P Gothic Fonts
fonts-umeplus - Japanese TrueType gothic fonts, based on Umefont and M+Font
fonts-vlgothic - Japanese TrueType font from Vine Linux
fonts-yozvox-yozfont - Japanese proportional Handwriting OpenType font
fonts-yozvox-yozfont-antique - Japanese proportional Handwriting OpenType font (antique kana)
fonts-yozvox-yozfont-cute - Japanese proportional Handwriting OpenType font (cute kana)
fonts-yozvox-yozfont-edu - Japanese proportional Handwriting OpenType font (educational cana)
fonts-yozvox-yozfont-new-kana - Japanese proportional Handwriting OpenType font (new kana)
fonts-yozvox-yozfont-standard-kana - Japanese proportional Handwriting OpenType font (standard kana)
latex-cjk-japanese - Japanese module of LaTeX CJK
latex-cjk-japanese-wadalab - type1 and tfm DNP Japanese fonts for latex-cjk
texlive-lang-cjk - TeX Live: Chinese/Japanese/Korean (base)
texlive-lang-japanese - TeX Live: Japanese
xfonts-ayu - Gothic 18/20 dot Japanese and ISO-8859-1 X11 bitmap fonts
xfonts-intl-japanese - international fonts for X - Japanese
xfonts-intl-japanese-big - international fonts for X - large Japanese
xfonts-jisx0213 - JIS X 0213 Japanese Kanji bitmap fonts for X
xfonts-kaname - Kaname Cho 12 dot Japanese Kanji, Latin 1 fonts for X11
xfonts-kappa20 - X11 Kappa 20dot Fonts (ISO-8859-1..4/9/10/13..16, Japanese) with bold
xfonts-mplus - M+ bitmap 10/12 dot Latin/Japanese fonts for X11
xfonts-shinonome - Various 12,14,16 dot Japanese Kanji, iso8859-1 fonts for X11
fonts-ipafont-nonfree-jisx0208 - Japanese TrueType font, IPAfont (JISX0208)
fonts-ipafont-nonfree-uigothic - Japanese TrueType font, IPAfont UI Gothic
fonts-mikachan - handwritten Japanese Truetype font
xfonts-naga10 - 10x10 dot Japanese and ISO-8859-1 naga10 fonts
How they map to UNICODE I don't know...