1. A lead distribution system to distribute consumer business leads from lead sources to a plurality of lead destinations, the system comprising: a processor configured to receive an electronic notification of a lead received from a lead source, the lead providing information about a consumer inquiry regarding an available product or service; computer-readable storage with which the processor is in communication, the computer-readable storage storing: information about lead sources from which the lead distribution system purchases leads, comprising, among other information, a cost score calculated for leads from the lead source, the cost score being based at least in part on an actual cost to purchase the lead from the lead source, wherein the cost score is further based in part on one or more business considerations associated with the lead source; processor-readable instructions configured such that together with the processor a scoring engine is implemented that calculates a margin score for each of a set of destinations that purchase leads, the margin score calculated as the difference between a revenue score assigned to each of the destinations and the cost score of the lead, wherein the revenue score for each destination is based at least in part on an actual price offered by the destination for purchase of the lead; and processor-readable instructions configured such that together with the processor a destination selection engine is implemented that selects one or more destinations to which to distribute the lead, wherein the selection is based at least in part on the margin scores.