Heater/A.C. Fan not blowing on lower speeds

I have a 1998 Oldsmobile Cutlass with about 64,000 miles and the 3100 engine. The fan for the heater and a.C. Will not blow any air on the 1 and 2 setting, anything above that and it works fine. I think it is the blower motor resistor. Am I correct? If so, is it located on the passenger side underneath the glove compartment? Any help is greatly appreciated! Thanks!