I Just got back from the German Audi House in Hassfurt (Audisoulja)! And Audi has released a new navigation disk that covers all of Europe, that is fully compatible with U.S. spec A5/S5's. It is a Little pricey for around 230 euros with VAT! But worth it......... for such a car!
And it was as easy as that! German dude slapped the disk in and it did some sort of update. I put in my home address, house number and all... and it took me straight to my front door.
The disk to get is:
Audi Navigation (MMI)
Digital Road Map Europe
>Version 2008...Duh (not the Duh part)
*cough* you can actually download this and burn it to disk *cough*
(if you know where to look)
and it works