1. A method of matching leads with consummated sales comprising the following steps: collecting selected leads from at least one lead supplier which identifies a group of prospective buyers for selected products or services; collecting a plurality of sales records having sales data information for consummated sales of the selected products or services, wherein the plurality of sales records are derived from multiple sales sources; and matching at least some of the sales records to the selected leads provided from the group of lead suppliers according to a predetermined matching confidence.