• Replace lost, broken, damaged or defective Microsoft software disks.
• Purchase product upgrades.
• Replace broken or defective Microsoft hardware products.
• Check the status on support orders.
• Order downloadable service packs.
• Replace missing manuals.

Note The current owner must be in possession of the product and be able to provide proof of purchase of all products when making requests for replacements through the Supplemental and Replacement parts team. The Supplemental Parts team provides service for the United States (U.S.) and Canada only. Submit all foreign replacement part and service pack issues to the appropriate local subsidiary.

via http://support.microsoft.com/kb/326246/en-us
In the United States at (800) 360-7561, Monday - Friday, 5:00 A.M. - 7:00 P.M. Pacific time zone.
In Canada at (800) 933-4750, Monday - Friday, 5:00 A.M. - 7:00 P.M. Pacific time zone.