I'm thinking that this is the sway bar or sway bar links. Does this sound right? This happens often and it doesn't matter which way I turn.
Based on my experience, I'd suspect the strut bearing plates if it has struts in the front (I'm not familiar with that particular model)... Those plates usually last about 5-10 years, then start falling apart. Makes snapping/banging/sometimes even grinding noises when turning. Eventually the steering will start to bind up and popping noises will start.
First thing i'd get checked is your wheel balances on all 4 tires. It's usually the most common cause of vibrations at higher speeds from my experience.