As far as I know there are no special rule changes when playing with 2 players. Everything works exactly as the rulebooks says.
However, you *can* simplify the handling of the visitors and the trees if you want; just use one of each color instead of three, giving it to the player in the lead.
And yeah, if you blow all your money on 2 tiles you're gonna be hurtin for a while!
Thumb'd you just for you avatar! Glad to see other people enjoy good music too...