1. Open the Performance Information and Tools option from control panel (or just hit [Windows Key] + [Break] together).
2. Click on the View and print detailed performance and system information link
3. Now you will see the following information, that you can event print out easily. This is how I found the model number for my laptop anyway...
4. For even more detailed information just run C:\Windows\System32\msinfo32.exe - or launch it from the msconfig.exe, Tools tab