I've heard only little Japanese music.
 
Some songs from about 10 artists.
 
But Matsui Keiko performed in a Finnish Jazz-festival.  I liked her performance a lot.

I also like Yoko Kanno. Actually, there might be interview of her in Hanami Web Top Story next month, but I cannot make any promises yet. She is interesting composer.
 
it is interesting to see of Beat Takeshi is going to use Joe Hisaishis music in the future. In his latest movie TAKESHIS he didnt use Hisaishi but another, yet quite unknown composer.
 
I know Matsui Keiko and her husband, who are both great musicians. I cant stop thinking about John Lennon and Yoko Ono and the resemblance of this producer-couple.

Jacke-san asked me just via e-mail about the Japanese music that I like (I think he wants to form a cover band). It's really hard to say! But I tell you what I said to him.
 
I have listened whole albums only by Ayumi Hamasaki (Album Best, Jacke-san gave it to me) and a group called Dido (Album name is Ksana and the artists behind are Ohtaka Shizuru and Kato Michiaki). It's from the 90's.
 
I don't like very much the high beat pop music.  
But it's ok sometimes and easy to find and cheers me up.
 
I like more old hit music, though the lyrics might be corny.. It's dramatic and melodic! I like old people's music... Something from 50's to 70's?
I like old Elvis style rock music no matter what the language.  
 
Enka sounds great
 
Mostly I've listened to the music from different movies. Kill Bill was a huge hit and I think that Tarantino has always had a taste for music.  Meiko Kaji's song was great and The 5.6.7.8's were funny!
 
Now my friends are into Naruto-series and the ending song by Akeboshi (Wind) caught my ear too. I would like to hear more Akeboshi. Now I've heard only two songs by him.
 
Yeah... and I kinda liked Gackt (Mars album)
I got a taste from my neighbours and school sempai who like some harder music.  
 
 
 

I like M-flo,Heartsdales,Tokyo ska paradise,Utada Hikaru,Yoshiki,Koda Kumi,Orange Range...... V

I found a new band for me: Garnet Crow.
 
They're usually known for their first single Mysterious Eyes, an opening for "Meitantei Conan" anime series, but I just love Rai Rai Ya and Timeless Sleep too.
 
その上、凄い美人だ、彼女たちは！ I though I'd best write that in Japanese, cause I wager I'll be collecting some flak from that. It just had to be said.  

My favourite Japanese singer is Nakamori Akina. I have liked her since 1983 on my first visit to Japan. I think she is an excellent ballad singer. I also enjoyed her in Tsumetai Tsuki drama. Even though she played a mean spiteful character, I think she did it well.
 
I also love enka! I know it's usually for obaachan, but I love it. I love Hikkawa Kiyoshi, Sakamoto Fuyumi, and Kazue Kaori.

I also used to feel enka is only for obachan but actually, I find enka can be very fashionable and pop! I have learned to appreciate the nostalgy feeling related to it.  
 
And as we know, soon the 60's style will become pop in interior decoration again. Add some Japanese enka and bright coloured flower vases, and we're there!
 
I love Nakajima Miyuki's "Kamome wa Kamome". The transparent and blue melody brings tears to my eyes. The CD where this superhit song is is called "Okaerinasai" published 1985.
 
Her voice is soo great and blue. Check out "Kamome wa Kamome"
http://www.youtube.com/watch?v=SEgP2P1OSi8