I have a 25 dollar gift certificate to the itunes store that I received as a gift from my junior/senior prom. I made an account and followed the steps but cannot use the card because the PIN won't work. It asks for an 8 digit PIN and the one that I scratched off is 16 digits long. What do I do?

Contact the customer service department. Please include the serial number (See the section above on locating the serial number for your card) on the card and fill out as much of the card activation code as you can.

Apple - Support - iTunes Store - Contact (http://www.apple.com/support/itunes/store/browser/)

That should do it for you.
Good-Luck.