how to show more than one marker for same geocode on www.LocalPriceMaps.com

I am trying to determine how I want to display information on
http://www.LocalPriceMaps.com

My issue is that i want to display lots of different markers
corresponding to the same geocode. I have somewhat solved this by
using a sidebar to show for instance , all listings for Microsoft
XBOX's in the New York area, but the thing is that while I have many
markers being listed in the sidebar I still only have one marker
because they all use the same geocode value.

Any ideas on how to better design this?