*sorry I meant money on the fan not resistor...
taken from a previous post on MSC:
"The heater fan probably needs replacing, it is a dealer item and is not cheap, but it is easy to change. Situated above n/s footwell, remove 3 bolts and the wiring plug exchange the unit and refit, you may need a new heater resistor located next to the blower and 1 bolt to change. Can be done in minutes."
heater fan = blower motor
Well Claire I think its safe to say that no air being blown is the motor rather than the resistor. However, when you do replace the motor and there is no hot air on max. etc. then it is probably the resistor as well.
Make sure you disconnect the battery negative before you go about it.
Sorry I cant be much more help.