Here are my tips...
25th Techno-Classica Essen – April 10th* - 14th, 2013
http://www.siha.de/tce_uk.php?m=1&ms=1
DTM racing... first race is on May 5th .2013 DTM - Hockenheim
http://dtmkarten.de/listing.php?knr=...FQNd3godqVkAWQ
May 12, 2013 -
BMW Welt, 4.0 Friends United
http://www.1addicts.com/forums/showthread.php?t=766766
24 hours of
Nurburgring, ADAC Zurich 24h-Rennen May 17- 20th, 2013
http://www.24h-rennen.de/Offizielle-...-05-2.2.0.html
Messe für Klassiker zu Lande, zu Wasser und in der Luft (Land, Water and Air!)
14. - 16. Juni 2013
http://www.klassikwelt-bodensee.de/kwb-de/index.php
IAA - aka Frankfurt Auto Show... Sept 12th thru 22nd, 2013
http://www.iaa.de/en/visitors/tickets/
I am sure I am forgetting some events.