Are there any mailing lists where I can ask questions about CAN?
The CANLIST mailing list is "...an independent discussion forum about Controller Area Network (CAN) and all related topics, especially questions concerning software tools and hardware configuration." You can sign up or search the archives from the homepage at http://www.vector-informatik.com/canlist/.
The Linux Lab Project is working on developing a CAN driver for Linux. They have a mailing list and archives which can be found at http://www.llp.fu-berlin.de/pool/newproj/CAN/.