There has been some discussion on CAN Bus but I cannot find it either. Simple answer is probably "not possible with a PICAXE by itself". There are CAN Bus interfaces to SPI or I2C which might help but a better bet would probably be a micro with in-built CAN bus peripherals.
I have have dealings with CAN as it is used on alot of the John Deer tractor and Volvo engines on generators I work with and it "CAN" be very tempremental. So good luk.