My product key for microsoft word 2007 is missing what can i do to get a new product key?

If you installed the software on your computer, search online for the 'PRODUKEY' software.
Download this FREE software, unzip it, and run it, to display the 25-character product-key that you used when you installed the software.

Or, if it's not installed, go to any computer-store.
You can purchase a 25-character product-key, on a piece of plastic about the size of a credit-card, for $99.