Added following link to Additional Resources / Downloads section.

ODB-II Codes translated

Don't know if there are similar sites like this but I thought this was a nice site. It explains a little about how the SAE Trouble Codes came about. However, the best thing is it has a place to enter your SAE Trouble Code and receive a description along with the equivalent BMW Diagnostic Trouble Code.

Example - Enter "P0172" and it will display:

SAE Code = P0172
DTC Code = 16556
Description = Fuel Trim, Bank1 System Too Rich