Ignition switch replacement?

I think I need to replace the ignition switch on my 1996 Sentra. My wife was driving it today and when she started home from work it wouldn't start. When she tried to crank it, all the lights and buzzers worked, but the starter didn't turn. She saw a little bit of smoke coming from around base of the wiper control arm. Any ideas?? If it is the switch, how can i be sure, and how do i go about changing it?

the ignition switch is in the steering column...i dont think its that. sounds like the starter.

could be like a bad ground shorted the starter solenoid. check to try and pinpoint the smoking. but its also possible the smoking thing isnt related. id check your starter first. run a cable from the battery positive to the positive post on top of the starter(the big post on top with a nut on it and a big red cable coming from it). the car should start right up.