OSM is just a data base. People have made geocoding that uses the OSM database. You can install it yourself (e.g. http://wiki.openstreetmap.org/wiki/Nominatim h

OSM is just a data base. People have made geocoding that uses the OSM database. You can install it yourself (e.g. http://wiki.openstreetmap.org/wiki/Nominatim http://wiki.openstreetmap.org/wiki/Nominatim ) or use a hosted version ( http://wiki.openstreetmap.org/wiki/Search_engines http://wiki.openstreetmap.org/wiki/Search_engines ) The advantage of OSM, is that if it's not returning the right data, you can fix it, and import it into your own hosted version.