Liyanda,
The Product Key was sent to the email address you provided when you ordered the CD directly from Microsoft. Try this link to follow up on your order details:
http://www.microsoft.com/genuine/selfhelp/orderhelp.aspx
Please be informed that the WGA Kit includes ONE license for XP Pro. This means that you are not permitted by the End User Licensing Agreement (EULA) to install that license on more than one computer at a time, so you cannot have the same WGA Kit license installed at the same time on both your computer and your father's computer. Also, please note that in some areas of the world, the EULA for the WGA Kit may have a supplement that restricts the installation of the Kit's License onto the original computer and prohibits moving the license to any other computer.
In order to view the EULA that applies to your installation, click Start>Run, then type winver, click OK, then in the resultant window, click on the EULA link to display the EULA.
