[Delirium-Zer0]

Keiko of globe's last name is Yamada, not Matsui. Keiko's a common japanese name for girls, best not to assume anything about who it is. Kinda like the name Hitomi. ~

Here is a short list of singers that have released things in the states (it's incomplete, but at least this is quite alot of them):
Seiko Matsuda
Toshi Kubota
Ken Ishii
DJ Krush
L'arc~en~Ciel
Pizzicato Five
Puffy (AmiYumi)
Tamaki Nami
X-Japan
Dreams Come True
T.M. Revolution
Utada

Compilations like Tofu Records' Neo Soul have other artists like Crystal Kay and Ken Hirai, and the soundtrack for the animated american movie Heavy Metal 2000 has the song "Inside the Pervert Mound" by Zilch, one of Hide's bands.

Also, puffy have three albums in the US. "An Illustrated History", a best-of that was only released for the american audience, and US versions of their albums "Spike" and "Nice".