Abstract: The disclosed invention provides a system and method for assisting a purchasing user in selecting a good or service from among a host of goods or services offered on a computer network-based purchasing system. The invention comprises a commerce promotion facility, which in turn comprises a server computer and a user computer at the purchasing location, connected to each other via a wide area network. The facility features the ability to assist the purchaser with making a product selection by asking the user a series of dynamic questions. The system is able to use the answers to the questions to limit the possible products offered to the user, greatly enhancing usability of the system. An embodiment particularly for the selection and/or purchase of drilling bits and oilfield services and equipment is disclosed.