LOST MY PRODUCT KEY!!!!! veryyyyy frustrated right now!

Someone PLEASE help me!

I started school in August. At the beginning of the semester, I bought Norton Antivirus 2011 (along with an HP Laptop). Once I tried to install the Antivirus software that I bought, the program displayed a message letting me know that i already had an antivirus program (also norton) pre installed on my laptop and if i installed the new one that it would stop the subscription that was already on the laptop. SO, since the laptop came with a 60-day subscription, I decided to just wait 60 days and let the preinstalled subscription expire before adding the software that i bought seperately..... Well, between those 60 days, I somehow lost the PRODUCT KEY!!!! All I have is the box it came in, and the disc! What do I do?