Creaking noise on 2001 Audi a6 Quattro 4.6

I recently started hearing a creaking noise on my 2001 Audi A6 Quattro 4.2. It began very subtle at first, and it only occurred during right turns. It has been about two weeks and the noise has gotten worse, it is much louder and it happens when turning both ways. I thought at first it may be a tie rod, but my old car had that problem and the noise seemed to be a different clicking noise. This is a creaking, like a casket closing...and It seems to be coming almost directly under the steering wheel column, I can feel the vibration from the noise under my feet on the gas pedal. I would really like to figure out what this noise is before taking it to a mechanic.