I do my rendering in Daz studio 3 advanced, I originally did it with the free version but later upgraded to advaced for the 64 bit capability. However most can be done perfectly fine in the standard edition.

I first downloaded it to use for reference purposes and possibly do a short story with it, needless to say I embraced the software and now do most of my work with it.

Daz studio is available here…
http://www.daz3d.com/

What you get is a few basics and you need to get a lot more models before you can be making comics with it. One the site the basic figures are free to download but you will need clothes and hair and stuff. Getting started and building a good library of stuff takes time. And potentially money, models are sold and don't always come cheap.

But there are a lot of free resources there are free models on daz3D, they do a new freebie every week.
Also worth checking out are these two.

http://www.sharecg.com/

http://www.renderosity.com/

and you can of course make your own.

Which isn't easy but well worth learning to do, I'm getting there slowly.
I'm relatively new to 3d and learning from the ground up.
I use blender as it's free and there are a lot of free tutorials for it.