if for example you search "widgets in 99999" you'll see the listings are farther up the list the closer to "ground zero" for the query...
I happen to live a couple blocks from the center of town and enjoy the top listing for that area...
however the listings do go on...(More local business results ») have you searched the complete list to ensure you're not showing "somewhere"? It may just be a case of "you're farther from ground zero than they are"
hope that helps...
[google.com ]
That might help.