Minn, If you've got an Intel based Mac you should be able to run Windows XP via Bootcamp. I've heard of a few of us Mac owners doing it that way and running PC flight sims without a problem. Unfortunately my poor old G4 Powerbook just isn't up to the task.........
It's unlikely that any of the decent PC flight sims will be converted to pure Mac format as the demand just isn't there (we're a rare breed!) and also now with the ability to actually run Windows on the new Macs.