First, check both the low and high speed fan fuses.  If OK, pull the  relay marked "Cooling Fan"  and (on the socket for the relay) using a piece of wire, connect the front middle contact to  the rear middle contact; the fan should run on its low speed (although low speed is pretty fast).  The same test applies to the "High Speed Cooling Fan" relay, except there is no "center" to the front and rear contacts (there's just the two front & rear contacts).  If you don't use some pretty stout wire, the wire will get hot in a hurry (lots of current being pulled here).  A quick test is all you need to confirm that the fan and resistor are OK. 

If the fan & resistor check out OK, you can disconnect the connector from the cooling fan switch (below the radiator), put the ignition switch in the run position and ground any of the three connections at the wiring harness connector  (not the connector going to the thermoswitch).  One wire (black) will give you nothing but the other two should give you low and high speed operation when grounded.  If not, suspect the relay(s); if so, then the switch is bad.