I would say that the best place for an ambient musician to live is anywhere with a relatively low cost of living, so that you could take on work that isn't overly demanding. Then you'll have time and money to actually spend on making music. The ambient community is for the most part, internet based now.
Having said that, I'm a hypocrite, as I have a demanding job and housing costs where I live are quite high.... but if I could work 25 hours a week and still have a roof over my head I'd gladly live in Winnipeg or something....
If you're in a large metropolis you can actually build a small ambient community if you have the willpower and staying power to make it happen.
I also think this is an excellent statement. If something you want isn't happening, make it happen.