We currently use Salesforce Maps, but before that, we used Mapline and liked it. It does not connect to your CRM but you export a list and load it into Mapline, then you can select the people you are interested in (like in a certain area) and export out the list again.

We use the built in mapping feature of Evertrue.  Works really well as you can filter down to the records you want and then toggle back and forth between the map and list view.  The list view then keeps the map view as a filter.  We viewed Salesforce Maps during demos for a new CRM and our team thought it was inferior to the Evertrue mapping feature.