A system for implementing a computerized prospect list service includes a server computer hosting a prospect list service accessible via client computers to a plurality of prospect list managers and a plurality of list purchasers and a database of information concerning prospect lists available from a plurality of list managers. The prospect list service includes a user interface having controls whereby a list manager or a list purchaser can access information concerning prospect lists stored in the database. The prospect list service is available via the Internet to assist a list manager in offering a prospect list for sale to a plurality of list purchasers and to assist a list purchaser in selecting and purchasing a list of prospects from a list manager.