Thank you peplin again for your interest in help with the CAN API development. Please, have just a little bit of patience. I hope to upload the CAN library and sample sketches on the next days. I am waiting on answers/revisions by Atmel/Arduino. And as I have said, try to build or have ready you own CAN transceivers shield; otherwise, it would be virtually impossible and even dangerous to try any communication test without it.
Like you and other Arduino users, I am more than willing to see a CAN API ready and all the discussion to come.