i have a 99 audi a6 quattro, when i turn, mostly to the left, theres this horrible creaking noise coming from somewhere, its not the interior im sure, somethings sounds really bad... please help thanks

 

Try bouncing the suspension with your hand on both sides, if you can hear a creak you need upper control arms. If you don't hear anything then lift the front of the car up, grab the tire at 9 and 2 and shake it back and forth. If you hear or feel a bang or play you need tie rod ends.
While you have the car up check the cv axle boots to see if they are torn.

 

i already tried bouncing the suspension on both sides, and it was creaking, so how much with a fix be for upper control arms be? estimate...

 

Don't buy the links at the dealer, you can get them much cheaper at www.ecstuning.com the average time to replace them is 4-4.5 hours.