Please help w/suspension noise

Hey, I have a question, its not about the SVX but i know some of you guys are mechanics and might now my answer. I'm driving a plymouth acclaim while I save up funds to get my car fixed (might be soon) on monday the rear of the car started making a high pitched tink, like a spring breaking under pressure, or like fishing line breaking only louder, every time the rear suspension flexes. At first it wasnt too bad doing its two to four times every time the suspension flexed, now it is doing it countless time every time, sounding more like a high pitched creek than an individual tink. Any ideas on what this is? I crawled under the car and i seemed to locate it around the spring area but I studied it for at least a half hour and found no sign of damage, but when im inside the car it sounds like its coming from the opposite side, or maybe even the middle of the rear. I'm getting very frustrated especially considering that its not even my car.