An electronic marketplace system embodies various inventions for assisting users in listing products for sale, locating the listings for a product, and performing related actions. A user wishing to sell a product can browse to an existing description of the product in an electronic catalog and then select an option to create a corresponding listing. If the user previously purchased the product via the system, the user may alternatively select the product from a personal purchase history. To create the listing for the selected product, the user preferably specifies the product's condition and a selling price. The pending listings for a product are preferably displayed or summarized on the product's detail page in the catalog. When no such listings exist, an option to preorder the product from an unspecified seller may be provided. In one embodiment, the electronic catalog also serves as a retail sales catalog of a merchant.