CD-key location

I'm getting ready to get a new HDD, because my old one is slowly eating itself . . . and I want to install DII on my new HDD, but I lost my CD-key . . . where can I look to find the CD-key that I am currently using?

On the cd sleeve to your diablo 2 disks, silly.

Additionally, you can download a cd-key grabber for it. It may be a little hard to find, and you really need to be careful about malware when you're downloading software to get cd-keys, because it's common there. I've done it before though with no bad effects.