Volumes 1-13 are currently out to buy in North America (and online through tokyopop.com) and Volume 14 is slated for release on November 7th 2006.
The series is also currently licensed through volume 19 and looks to be a pretty long series.
I don't know about you, but this makes me happy ;D
If you love the art in King of Hell, also check out Warcraft: Sunwell Trilogy as Kim Jae-Hwan is at it again ;D
Also, if you're like me, you've probably been wondering if any of the korean based manga would ever be animated. This has become a distinct possibility now that korean writers/artists have become more prominent in the manga revolution.