Where can I buy a CD changer bracket for the trunk?

is your local audi parts department refusing to sell it to you?

try a junkyard, since a lot these cars get totalled in the front. here's a list, start with Dad's
 

check under recyclers/dismantlers...<ul><li><a href="http://www.audifans.com/parts-type.html">http://www.audifans.com/parts-type.html</a</li></ul>

Wna the bracket or the kit?
 

clair.com has the factory kit which includes the bracket and the cd holder and all of the screws ect to make the install like it came from the factory. Well worth while, costs about $65 and takes about 30 minutes to install.