Heres some FREEWARE Australia scenery
NOTE: I think you have to download some of their OBJECTS 1st tho so the scenery will show up correctly, but the OBJECTS appear to be FREEWARE too !
check it out !
http://www.vectorlandclass.co.nz/index.php/downloads/airports
Heres another one I found too,,,
believe its for Phildelphia Airport , LOOKS High Quality too !!!
Philadelhia Link : http://www.sunskyjet.com/scenery2.html