Dell does not maintain a database on the Office products they sell so Dell will not  (can't) help you. If you don't have a product key to install it, you can install the free OpenOffice suite of programs which are equal to and compatible with MS Office.  www.openoffice.org  
I have lost my product key and there is no website with a valid way of getting a replacement one! can anyone help?
Microsoft office 2007product key replacement