I've looked without much success but if we could start building a list of websites/forums for MMO games and start writing on them about Aces High and how great it is...
...it wouldn't be any help.
The problem with AH isn't advertising, it's the actual game. Part of the problem is that the only people left have been playing forever and don't recognize the issues.
This is what happens when you show someone with interest in flight sims and MMO's (but dissatisfaction with the arcadeyness of WT) Aces High, based on experience:
Reactions, in order:
"Wow this game has really bad graphics"
"Why do all of the planes have the same sounds"
"I want to fly plane * (let's say Bf 110), it's my favorite -- why does it look like this, what is this model 15 years old? (Joke's on them, it is)"
"How do I control the radiator flaps, mixture etc.?"
"Oh."
"No, it's just that you said the game was pretty realistic."
"Is there just some sort of tutorial I can bang out for a while?"
'Do you want to try flying AH again?'
"Nah"