Just to be clear here: no one here on this forum WILL, SHALL or SHOULD give you their CD key or direct you to a site which would. Why? It's illegal, and the site staff would be held responsible. Personally I'm not interested in having a criminal record.
What you can do, however, is contact Lionhead tech support, photograph your game disk so the writing around the hole in the middle is readible and send the pictures to them. They should supply you with a new serial.