Use shape to identify data in Bubble Chart

[goggem]

I have a bubble chart.

I use shapes, particularly the round shape, which I set to partially opaque and then use it to highlight data in the bubble chart.

It looks like this:
http://img834.imageshack.us/img834/1632/bubblez.png

I would like to be able to generate a list of the points that are highlighted by the circle.
Using vba is perfectly okay.

Thanks very much,

Adam