Use the contact information for the Apple Online Store.
The agents there will either handle it personally or forward your call to the appropriate party to help you.
Apple Online Store
Apple.com is a convenient place to purchase Apple products and accessories from Apple and other manufacturers. You can buy online or call (800) MY–APPLE (800–692–7753).
You can get information about an order you placed on the Apple Online Store through the Order Statuspage. If you prefer, you can also get order status or make changes by phone at (800) 692–7753.
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How to Buy for Education
If you are a student or teacher, visit the Apple Store for Education or call 1–800–692–7753.
[same number as above]
If you are buying on behalf of an educational institution, visit the Apple Store for Education Institutions or call 1–800–800–2775,
7 days a week from 9 AM to 6 PM central time
7 days a week from 9:00 a.m. to 6:00 p.m. Central time.