What are the locations of the various theme files in Windows 7?

Regional themes (Country themes):

%SystemRoot%\Globalization\MCT

Installed themes (Aero, etc):

%SystemRoot%\Resources\Themes

Per-user installed themes (including pre-installed from OEM):

%LocalAppData%\Microsoft\Windows\Themes

Current wallpaper file (if any):

%AppData%\Microsoft\Windows\Themes

User installed themes are located on %AppData%\Local\Microsoft\Windows\Themes; in Windows 7 they are on %userprofile%\AppData\Local\Microsoft\Windows\Themes