Running OS X 10.5.8 - purchased OS X Mountain Lion 10.8

Yesterday I ordered the new softward package OS X Mountain Lion 10.8 and today I received and email notificaiton for me to redeem my software package using the App store. I received a second email with my password. It ask me to redeem my software using Quick Links and apparently even when I do a search, I can't find it. Is it that I'm using and old system (10.5.8)?