Depending on how you bought Windows, there are three main places to look:
If you bought a physical PC with Windows 7 pre-installed, look for a "Certificate of Authenticity" (COA) sticker on the bottom of your laptop or the side of your desktop tower. product key for windows 7 ultimate 64 bit | FullPCSoftz
If you purchased a digital copy from Microsoft or an authorized retailer, the key will be in your digital receipt. Depending on how you bought Windows, there are