Can anyone out there help me find an answer to my boggling question...Can you paint a pre-exsisting roof? If so what type of paint would you need and is there any priming involved?

Simpy put, NO. I have seen many roofs painted however. It looks great for about a week, or until someone walks on it and the surface wears and the old colors come through.

You can if the roof is a flat roof re-coat it with a silver coating used to reflect heat and UV rays. But that is really not paint but an asphalt coating with a silver color added.

Many years ago I was on a roof that a customer had painted. The were told by the company that did this that they had some sort of product that would add years to the life of the roof while making it look new again. This snake oil salesmen took their money and was never heard from again. Anyway when I walked on the roof for the inspection, and once I got back on the ground. You could see every footstep I took on the roof as though someone took those foot things used in learning to dance. all over the roof. The paint did nothing to fill the cracks and wear that the roof had. Looked nice from ground, but up close did nothing to make roof last longer.