I only just started playing AH this summer. I've found it to be a source of stress relief, and at times a source of palm sweat and abusive language.
I've learned the game through various sources, mostly online videos and trial and error in-game. I've been informed multiple times (upon asking like a noob) that there are trainers available in the TA but they are volunteers and not always available when I'm ready to jump online. For me the LWMA WAS my training arena; it just so happened that training used live rounds
Apart from the basics of flight which is THE most important aspect of this simulation because the physics in this WWII combat sim are unlike any I've played before (IN A GOOD WAY). I found it very helpful to fly offline without the threat of being shot down. It allowed me to practice AND shoot down some aircraft, so I'd bounce back and forth until I had a good feel for a one or two aircraft.
I fly Knights in the Late War Main Arena (LWMA), and over time if you are a new player, and ask politely on range usually another pilot will help you out. The best training I've had thus far in game has been by joining larger missions and emulating the other players. Don't underestimate the practice that comes from attempting to fly in formation (even with the .wingman auto-pilot command at times).
The 
BEST way to help a new player and retain them as a subscriber is to make their experience enjoyable. Take 20 minutes to speak with a new player AND fly with them. If a player is sticking close to you, don't get upset that they are following you, use them, ask them to stay high and watch your six where it's safe but they still feel as if they are PARTICIPATING.
As with me, it was the interaction with other real players which got me hooked. If it weren't for the "Renegades" squad and all the help TripleS, Dragger, 999000 provided me, I doubt I would have renewed my subscription.
Having the guys which I felt were "good players" tell me good job, or thanks for getting that guy off me made me tell my friends outside of the game how much fun the game was.
As for the OP, The forum is always a good place to find information, IF you can find it among the irrelevant postings... For me it was watching videos online, mostly VuduVince's, and then back to the forum/website for more complicated information such as .dot commands, or building hardness (how many bombs to destroy), etc.
1. Identify new players
2.
make an attempt to engage them positively,
3.
Provide impromptu training in form of Q & A4.
Mold them into Aces!
