Product key

I just recently bought a laptop with Vista on it. I have the product key on

the bottom of my laptop, but everytime I go to word or any other office 
program it says invalid key. I have tried to contact the place where I
bought 
it and they said that it should work, and if it doesn't I need to contact 
Microsoft, which I have done and they said that there isn't anything they
can 
do for me without purchasing a new version of office, even though i
purchased 
it when i bought the laptop. Is there any other way I can get a product
key 
from microsoft or some other forum?