akumetsu.com

they have a huge amount of manga, like 100 series.

But what sucks is that you have to join hentaikey.com
you have to join.....
but its free, just need an email (fake one or not)

http://akumetsu.com/main.php?page=join.htm

then click on the free section.

There is this nice guide that will guide you through the sign up process. also its free...