Where is the transfer case switch on a 1993 Chevrolet Blazer S-10?

The 1993 Chevrolet S-10 Blazer's transfer case switch isn't a single, easily identifiable switch like a light switch. Instead, it's integrated into the floor shifter. There's no separate switch for the transfer case itself; the shifter directly operates the transfer case mechanism.

You'll find the shifter on the floor of the vehicle, usually between the driver and passenger seats. It'll have positions for 2WD High, 4WD High, and likely 4WD Low (though the exact markings may vary slightly). The act of moving the shifter to these different positions is the "switch" function.