Brake Lights not lighting up

So you have no brake lights at all? I would start with checking fuses, then start probing around with a test light if the fuses are good. Before and after the brake light switch, and then back at the bulbs and make sure you have power everywhere.
 
Have you had the dash apart recently? Grounds are a possible problem.

Unplug the brake light switch under the dash, put a jumper wire on the plug with the wires, you should get brake lights, if you do then you have a faulty brake light switch.