You can't. Data is always submitted back to FormsCentral servers. Can you provide more detail on why you want the submit to go somewhere else.
Sure. Because it is a scheduling form and I want the filled out form to be forwarded to our scheduling department email.
We support email notifications. When the user submits the form data the data will be stored on our server and an email can be sent to anyone who has access to the responses.
This FAQ explains how to setup email notifications: http://forums.adobe.com/docs/DOC-1424