There's a total of 11 issuses of LW 2100, or they also have it compiled into 3 graphic novels.
Darkhorse still has them on their website for retail, $2.99 per issue or $12.99 for the graphic novels.
I've had these sitting in my collection for a long time hadn't thought about them until I saw the minis and it was like a lightning bolt when I made the mental connection. It's a great series and I think I'll be giving it a re-read.
My personal preference is for the individual comics over the graphic novels, the reason bing is that the colors in the comics tends to be a lot richer and less glossy. Graphic novels are great for teh price and having everything compiled in one place but the paper is almost always glossy and it doesn't have as vibrant colors and the colors aren't blended nearly as well. It's a minor thing but I tend to be picky on small details.
The original lone wolf and cub series is great, although best picke dup in graphic novel form, it's black and white and on normal comic paper so no quality differance. Also finding the original issues is a chore and a half, not to mention very pricey as the comic version has been out of print since '85. The graphic novels are great and once you start on the first you'll need the rest.
Blade of the immortal is another series that dark horse publishes that's made out of pure samurai win.