Hi Lukas and Dan,
I also would like to have an upper level library for both J1939 and OBDII. I ordered an Arduino DUE CAN-Shield from Dan to test the CAN functionalities from the current CAN Library. When I understand how this is done I hope there is a way to work together here on the Forum to develop an OBDII and J1939 upper level Library. That would be so great. For OBDII there is this library from SK PANG (distributed by Sparkfun too) which is used on an UNO: http://skpang.co.uk/catalog/arduino-canbus-shield-with-usd-card-holder-p-706.html
I am not sure how good this library is, but maybe it is straight forward to port it on top of the standard Arduino DUE library.
Somebody experienced with this SK Pang shield and the OBDII library?
Pieter