Oh my goodness, I have been inundated and feel like a bit of a fraud
There's definitely no secret mafia except for the info that's exchanged face to face as far as I'm aware.
Publicly, the best current info on decent routes and fares AFAIK is available on the BAEC forum on FT. They call it Tier Point runs.
It won't spoon feed you and the BA earning tables are slightly different. IMHO it makes good reading, particularly since the advent of the US Airways routes.
And apologies in advance to anyone who's already all over this and was looking for something better.