I had the same issue with my TT. It's easier to just buy the complete pillar cover and the black piece comes with it. I picked mine up new for $120.
Wife's Black 2008 TTq 3.2, Black & Alcatara interior. Not sure how but found this little piece broken off, so the Parcel shelf cannot be used at this time. It's black, can supply a pic if really needed but its a pretty simple part.
Get the part # and go to this site:
Mine was standard material and list price was $250'ish. They wanted quite a bit more for labor to install it.
It was pretty easy to take out the old one and put the new one in. About 1 1/2 hours with a little patience.