You could join our corp. There are a lot of asteroids in our home systems, and they nearly never get mined. I find medium and large Grav sites with the best ores in the game all the time, but since no-one is around that mines them they sit unused until they despawn. You could always come and mine those. I can't say that I will help you, but I have sat around and provided protection for miners once before.
As for an actual mining corp, I am not really sure about that. There were quite a few members of our corp that mined on a regular basis when I started, but they haven't been on in a while. I never see miners around where I live, so I can't even tell you of any other mining corps.