A broker facilitates customer purchases from merchants. Shippers ship shipments containing the purchases from merchants to the customers. A shipper identifies a shipment using a shipment identifier. The broker uses the shipment identifier to obtain the status information for the shipment from the shipper. The broker analyzes the status information in combination with other information to calculate an estimate of the time that the shipment will arrive at the customer's address. The broker sends an electronic message, such as an email or text message, to the customer prior to the estimated shipment arrival time to inform the customer of the impending arrival. The customer can thus arrange for someone to be at the shipping address to receive the shipment at the estimated arrival time.