The present invention includes a method for transacting business over a network between multiple buyers and sellers. In an exemplary embodiment, the invention operates within an improved extranet system which is a secure, limited access network which operates within the larger public packet switched network (Internet) and allows only registered buyers and sellers to access the website while the system communicates with, and takes advantage of, existing credit, billing, collection, clearinghouse, insurance, transportation, tracking and banking systems. The interactive database includes real-time information in connection with a transaction, where the buyer submits a request for product and the request for the product locks out the requested product from selection by any other buyers.