Systems and methods for shipping a package from a package sender to an intended recipient, utilizing Internet communications to place shipping orders, request on demand package pickup, maintain and utilize pre-stored profile information, view shipping history, track orders, etc. A package sender with an Internet-accessible computer accesses an Internet site and associated shipping system operated by a shipping service provider. The package sender enters information required for shipping the package, including shipping options and methods for payment, and the shipment transaction is validated. If the transaction is validated, printer indicia are communicated to the customer's computer, which is enabled to locally print a prepaid label containing special machine-readable as well as human-readable indicia. The shipping service provider acquires the package by drop-off, standard pickup or on call pickup, scans the machine readable indicia, verifies other indicia of authenticity, and processes the package in accordance with information encoded on the label.