25. A system for providing a legitimacy rating of a content source associated with a document, comprising: an input receiver for receiving from a user a request for a document associated with a concept; a selection processor for selecting an electronic document from a document provider based on relevance to the concept, the electronic document associated with a content source; a legitimacy rating processor for determining a legitimacy rating of the content source, wherein the legitimacy rating is based on a history rating and a transaction volume rating and wherein at least one of the history rating and the transaction volume rating comprise a metric that is normalized based on at least one of history ratings and transaction volume ratings of a plurality of content sources who provide documents to the document provider; and an output device for providing the electronic document and the legitimacy rating to the user in response to the request.
25. A system for providing a legitimacy rating of a content source associated with a document, comprising: an input receiver for receiving from a user a request for a document associated with a concept; a selection processor for selecting an electronic document from a document provider based on relevance to the concept, the electronic document associated with a content source; a legitimacy rating processor for determining a legitimacy rating of the content source, wherein the legitimacy rating is based on a history rating and a transaction volume rating and wherein at least one of the history rating and the transaction volume rating comprise a metric that is normalized based on at least one of history ratings and transaction volume ratings of a plurality of content sources who provide documents to the document provider; and an output device for providing the electronic document and the legitimacy rating to the user in response to the request. 27. The system of claim 25 wherein transaction volume rating of the content source is based on the number of electronic documents associated with the content source that are provided by the document provider.