Did you check the fuse? Do you have 12v at the blower motor (orange/black wire under the battery) when the climate control is in the defroster or heat position? Another place to check is how the resistors look. They are found by removing the red panel on the passenger side of the heater box. The plug going in to the resistors also should show 12v on one, then two, the three wires as your increase your fan speed on the climate control.
I just finished chasing this problem down on mine after installing a blazer blower motor in mine. Turned out that the switch plug was not completely connected to the fan speed switch. It had come loose driving.
Anyway I hope this gets you started... No pun intended..