The ability to manually specify locations for unmatched addresses by clicking a location on the map does not currently exist in ArcMap.
The Pick Address developer sample demonstrates some of the geocoding customization capabilities of ArcObjects.
This sample is a simple tool, allowing users to choose a location for unmatched addresses by clicking a location on the map.
To download the Pick Address sample: Click on the link in Related Information to go to ArcObjects Online. Click on Query the Samples and in the By Category drop-down list, select Geocoding.