How to Determine the Serial Number
Find the serial number of your Apple laptop or desktop.
Click the Apple icon in the top left corner of screen and select About This Mac
Within the "About This Mac" window, click on the "Version" line twice to display the Serial Number.
Find the Serial Number of your iPhone, iPad, or iPod Touch.
From the "Settings" app, tap "General" and then select "About".
Scroll down the page a few lines and you will see the Serial Number listed.
iPads and iPods also have the serial number engraved on the back of the device.
iPhones also have the serial number listed on the SIM card tray.