How can I set an image for each category?

Hello,
I'd like to set an image for each category.
I've found a few plugins and the one I was nearly able to get working was
http://wordpress.mfields.org/plugins/taxonomy-images/
Before I continue trying to set plugins, is there an easied option in Atahualpa?

I'd like to have an image appear in each post similar to
http://digwp.com/
I believe they are using the featured image function, which I was not able to get to work.
I do manage to add it in the post, but it does not appear in the live post.
http://en.meetnihon.org/

Thank you

Update I was able to get a similar plugin to work, but now waiting from the developer to get back to me on increasing size via the short code [print-image]
http://wordpress.org/extend/plugins/category-image/