finally after many headaches, including two Ubuntu reinstalls, I found out the easy way to get mono installed:
the detailed instructions are here:
the installer is just what you would be used to in Windows, simple "next, next, next, finish"
it even comes with Mono Develop, the whole thing, really to be used
at least I learned how to compile and install packages manually :)
next I'll be talking about my experiences with Mono Develop... I would like to install Chrome too