Hello,
You don't need to provide a host for the geocoding API. This is an optional field when registering for a general access key and while we would be happy to know where you're using the API, you won't be denied the key if you don't provide it for geocoding.
You register for the key here:
https://developer.yahoo.com/wsregapp/and select the first option for authentication method: Generic.
You can use the same key for all of your environments (development, staging, production, etc). Hope this helps and happy developing. ttyl,
mich
