you do not have to download this dependency in order to make fileUpload working. To make working any of the components I recommend you to follow the Developer guide, section 2.1.1. Project libraries and dependencies.
The best way to bring dependencies into RF project is to use Maven, however, you can download mentioned libraires manually. For me for example, it is most easy to fetch all the required dependencies from already existing RF apps. So I download richfaces-showcase-tomcat6, and decopress it, to access required libraries from WEB-INF/lib.
Was that helpful to you ?
You are altogether right! The problem I had regarding with rich:fileUpload was related with the richfaces style, I mean, I was testing fileUpload in a lonely component inside a ui:define and for some unknown reason, that component wasn't inheriting the default richfaces style. I don't know why!!!
So after spending too much time trying to find what was wrong I put the component inside of a master template page I have in my project and that way I could get the fileUpload component working as the Showcase. That's really weird 'cause I have others pages working alone and they are receiving the default richfaces style.
But at the end I have to say thank you for your time. = )