The Squeaking is killing me

Hi all,
I have a 2003 Chevy Blazer. Recently when making slow left turns I get a high pitched squeaking sound coming from the front end, i think, but it stops once I straighten out again. I cant get it to replicate the sound when Im not driving. Anyone have any ideas on what this is?

Front Wheel Bearings are going bye bye...

Front Wheel Bearings are going bye bye...
I thought that was more of a hum???

I had 1 wheel bearing do something simular, but it was a rear wheel bearing on a FWD

I agree , wheel bearings likely loose or worn , allowing the brake warning indicator to rub on the rotor .Rob

Thanks for the info on the bearings. Ok in all honesty I dont know much of anything about repairs so I am going to have to take it in. Few questions if anyone could answer for me... How critical is it to get fixed, it just started about a week ago and I have a trip coming up tomorrow that involves about 3 hour drive, would I be ok to wait (in most cases anyway). Second question, is this an expensive repair? Sorry if i missed it before but its a 4wd SE.