Hey Red,
Clam's right, from our perspective it looks like you're all set and ready to go. But just incase you're not, here's how to find it:
Your CD key is located in your My Games section of your steam app. Open your steam account, go to your my games tab(same place you'd go to start the game), scroll down until you find TANE, then right click on it and select the CD key button. I can't remember what its named, something like "Display CD key or Serial Number". Anyway, a window will pop up displaying your CD key. It should have a button that lets you copy it to your clipboard.
Oh yea by the way,
Nice to meet you and welcome to the community!