The address on the envelope:

Audi AG
Postfach 1444
74148 Neckarsulm
Deutschland

but there's an another one above my address:

Audi AG
Kommunikation Motorsport
D-85045
Ingolstadt
Deutschland

WOW !!! that is a great success !

What address did these come from or do you know ?

Hi vacsad :)

Thank you for your feedback {up} Great Success :P

You have been added to the list for the $10 gift certificate.

Fanmail 8)

Wow !

I've sent an autograph request message to Mattias Ekström on his Facebook page ( https://www.facebook.com/mattiasekstrom.racing but I think Audi Sport's FB page is better for this purpose https://www.facebook.com/AudiSport ) at 2013. 08. 23. and a few days later he replied me, promised me a signature.
At 2013. 09. 06. I've received a mail from Audi Motorsport with signed photos of EVERY AUDI MOTORSPORT DRIVERS FROM EVERY IMPORTANT RACING SERIES!!!!
17 autographs!!! And a nice letter :)
And a big info package about Audi Motorsport's interests in racing (the pack is originally intended for media workers)!
[b][u]And the best part: all autographs looks authentic![/u][/b]
I can't say thank you enough, Audi Motorsport!
A little list of autographs:
Adrian Tambay - DTM driver (German Touring Car Championship), son of former F1 Ferrari driver Patrick Tambay
Allan McNish - WEC (World Endurance Championship) driver with a chance of winning championship this year, former F1 driver (Toyota), 3-time Le Mans 24H winner
André Lotterer - WEC driver, champion in 2012, 2-time Le Mans 24H winner
Benoit Tréluyer - WEC driver, champion in 2012, 2-time Le Mans 24H winner
Edoardo Mortara - DTM driver, 2-time race winner, F3 Euroseries champion 2010
Filipe Albuquerque - DTM driver
Jamie Green - DTM driver, overall 3rd 2012, Formula 3 champion 2004
Loic Duval - Endurance driver, Le Mans 24H winner 2013, SuperGT champion 2010
Lucas di Grassi - WEC driver, former F1 driver (Virgin F1), 2-time Le Mans 24H 3rd
Marc Gené - WEC driver, former F1 driver and tester of Ferrari F1, 1-time Le Mans 24H winner
Marcel Fassler - WEC champion 2012, 2-time Le Mans 24H winner
Mattias Ekström - DTM driver, 2-time champion (2004, 2007)
Miguel Molina - DTM driver
Mike Rockenfeller - DTM driver, very good chance of being champion this year, 2-time Le Mans 24H winner (2005 and 2010)
Oliver Jarvis - WEC driver, 2-time Le Mans 24H 3rd
Timo Scheider - DTM driver, 2-time champion (2008-2009)
Tom Kristensen - WEC driver with a chance of winning championship this year, 2-time DTm overall 3rd, [b][u]9-time[/u][/b] Le Mans 24H winner (My favorite from this pack!)

[img]http://surfmypictures.com/photo/2919c6cf2e49c034/44a9e/1851237573.jpg[/img]
[img]http://surfmypictures.com/photo/2919c6cf2e49c034/7e0e0/668784011.jpg[/img]