Customers make purchases from online merchants using personal information, such as payment and shipping information, stored with an online information service. The merchants may optionally report information about each customer's purchases back to the information service, which may incorporate the information into a history page that is accessible to the customer. The information service may also use the aggregated purchase history data to generate an “interests” profile for the customer, which may be disseminated to the merchants and used to customize their web sites. The web pages of the merchants may include a reference to an object, such as a graphic, that is served by the information service. For customers that are registered with the information service, this object may be customized with the name of the customer, and may be selectable by the customer to make single-action purchases.