Over at the LX Forums there's a member who created the TranZformer. It's a CAN device that allows for some neat functions through the use of steering wheel buttons.

Since our systems are so closely related, it may be of technical advantage to ping him, in addition to what you might find here.

Also there are several wiki pages out on the Web which take you through the basics of identifying signals, etc.

Good luck, and keep us posted on your progress!