Where are the drivers for Windows computers located on an Android phone? Im talking about the drivers that install when you plug your phone into a Windows computer.
They're not stored anywhere on your phone. Windows finds and downloads them from Windows Update when you plug your device in. If an appropriate driver has already been downloaded and installed previously (or shipped with the Windows installation), it will use that and skip the download step.

Without Internet, and in the absence of an appropriate driver already being present on disk somewhere, the driver installation will end up failing.