Romeo Tango
When you say "Each country publishes a document called the "AIP" or "Air Pilot" which includes, amongst a lot of other stuff, what they want to know and who to ask", are you saying that AIP stands for "Air Pilot" or that some countries don't call it the AIP?
I have only ever heard of the AIP as short for Aeronautical Information Publication. In the US I had a book called FAR/AIM (Federal Aviation Regulations/ Aeronautical Information Manual).