air conditioning drain plugged

I have a 1997 Blazer where it doesn drain water out of the air conditioner. I can hear the water slushing around inside. Where is the drain located and what does it look like? It used to work but now I still hear the stuff inside, but when I turn on the blower, I get nothing. I hear the fan running, but no air is coming out. Thanks for the help.

Anyone? I know it is on the drivers side. I think you have to reach
inside the wheel well behind the flexible flap and underneath somewhere. I was told it is like a rubber duck bill type thing. I figured the rubber maybe stuck together or have some dirt in there. Does anyone have any suggestions for me? Thanks!