There is a little bit dust laying on this this sources. For current sources please install subversion aka svn if you haven't it already. Then get the current development trunk with
svn co h t t p : / / w w w . rocklinux . net/svn/rock-linux/trunk rock-linux
It is mostly stable, specially crystal and bootdisk target. The project prepares a new release, so you can help if try it out. A lot of more information and how to start with the source is found on the homepage r o c k l i n u x D_O_T o r g .
Oh, no urls alowwed for me, so please remove spaces.