referencing data (pushpins)

I have MapPoint open, and a COM-Ad in to encirlce pushpins loaded onto the map, and have the code compiled into a com add-in, which is added to map point via the [tools]==>[com add-in].

I'm not sure how to reference the "MapPoint.DataSet" of the currently loaded map so it loads the pushpins and encirles them?

Any ideas?