I really really need to know the email address to contact Steam about my Black Ops disc problem!!

Wow, my black ops disc code isn't working but that's because I used it on another account and on taht other account for some reason I cannot retrieve the username and password

So I really need to email them and if I don't I will die from lack of black ops!@!@!@!@!

lol not really but I'll be sad please help out an old friend