Sounds like one of your accessory drivebelts. There are two drivebelts coming off the crank pulley: one runs your A/C compressor and the other runs your power steering pump and alternator. Did you pop your hood and take a look? The latter belt may be very loose or it may have broken.
If the belt is indeed gone, you'll need to fix it ASAP; even if you think you can handle having no power steering, without a running alternator your battery will die after an hour or so, since it's not meant to handle the load of ignition.