Thanks. I found -
http://matrix.itasoftware.com/ recommended here on a different thread and that shows the fare buckets.
Interestingly one of the trips i need to come back to Aus for was the same price through AA or QAN and was a QF codeshare, so if i booked as an AA flight i would get the points/miles.
I think I will wait until we are over in the US and then sign up for the AA program. All of our flights (except the initial move there) will be Jan - April next yr.
One final question; if i book tickets in my wifes name do i get the points for her travel also, or is it just for the one person?