Ktgoss

I purchased "Sins Of A Solar Empire" at a retail Superstore before I left for Afghanistan in the spring last year. I never got around to installing it until I was in Afghanistan so I was unable to register it. Now I am back but my C.D. box has not got back to me yet and will not be for some time if at all. So my question is how can I find my serial number on my computer? I know it must be somewhere on my hard-drive right? If so were can I find a "Key Finder" that can get it? I have tried some