1. A method for detecting and managing unauthorized use of cloud computing service resources, the method comprising: identifying, at a computer system, a plurality of Web resources that have been accessed by computing devices from within an internal network; obtaining, at the computer system, Internet protocol information from a network component of the internal network, the Internet protocol information being used to determine whether each of the plurality of Web resources is a cloud computing service resource; and blocking, at the computer system, access to a cloud computing service resource of the plurality of Web resources upon determining that the Internet protocol information identifies the cloud computing service resource as being unauthorized.