still have engine squeaking

I feel like I'm driving a beater around lately. Just this year I've done brake pad/rotors, water pump, ps pump, and although all those things needed to be done, the fucker is still squealing. It sounds like a pulley bearing, not a belt slipping. I've tried listening for about half an hour and it sounds to me like either the tensioner pulley, or the idler pulley. Does anyone have any tricks to find the squeaky wheel? Would a stethoscope help? I've found about equal amounts of post around the web claiming each of these pulley failed in their car. thanks,
bill

The stethoscope works pretty good. My buddy used his on my s10 an found the noise right away.

or put you ear on the handle end of a screw driver and touch the blade to different stuff. works like a stethoscope.

Yeah what both of them said.

X3 That's what I gotta do at work too. Either that OR spray a little brake cleaner on the belt, but not too much the belt could slide off. Sometimes that can help make the noise sub-due for a second to see if that pulley or idler pulley or something is making noise.