>FedEx may not have it. All thirtd party needs to create such webservice is the way to query FedEx for tracking info.

Ok, but they have the needs to find a way to extract that information. One possibility is that they are reading the HTML from the page, by the use of the form result, and returns that into a simple Web Service method. The other possibility, is within the FedEx installation package that could be installed locally, assuming its data would be readable from the external.