Instructions
Click the "Start" button located on the Windows taskbar at the bottom of the screen.
Click "Computer."
Double-click the hard drive that "Fallout 3" is installed on. For many users, this is the "C:\" drive.
Double-click the "Program Files (x86)" folder.
Double-click the "Bethesda Softworks" folder, followed by the "Fallout 3" folder.
Double-click the "Data" folder, followed by the "Meshes" folder. In each of these folders, there are the various .nif files for "Fallout 3."