Thanks for the quick response. I have a couple of follow up questions:
1. Can I use the World geocoding service without an online account? The link you posted gives me results, implying that it would not be required.
2. If the World geocoding service is used without an online account, how does ESRI track your activity and bill you accordingly?
3. If an online account is required, then do I need to write an app that is hosted by ESRI, that is little more than a wrapper around the geocoding service? Much like the service, the app would accept addresses from an external program and then output the data returned from the geocoding service back to the external program. Can this be done with ArcGIS online?
Thanks again.