I have a US market 22' Subaru WRX.
I don't have an exact answer for your second question.
I am referencing a config file (.yaml) from an opensource project. In addition to PIDs, it contains base addresses, byte order, data length, memory name, memory type, scales, operations, coefficients, parameters, units and so on.
Everything is specific to my vehicle, but I think its using memory addresses, from its use of memory base address, length, and offsets, instead of CAN frames. So it might be non standard OBD2, but I could be wrong.
I can monitor CAN bus traffic, for example using Savvy CAN, to see Frame IDs and the entire 8 x 8 byte packet, but I am having difficulty determining where an individual message starts and stops when reviewing logs.
Other than the Wikipedia article, are there other resources detailing OBDII that don't require purchasing the standard? Nothing illegally obtained and posted online either. I don't like that the standard bodies charge, huge sums of money to access standards, but I don't want to steal it either.