OK. I asked because I really don't know very many Australian plants, although some of your pictures could be imports. Here's a link to a site showing Q. trojana. http://oaks.of.the.world.free.fr/quercus_trojana.htm
I don't think there are any pictures of it here at DG. In fact, I think there was not even an entry for it until I added it last week. I added it because someone just sent me some seeds of it from California, but it's an Asian/European oak. So it's unlikely to be what you have unless it's cultivated.
Hi, I'm not familiar with Australian trees, but as someone said, some of your trees may be imports. My guesses are:
#1 Sawtooth Oak, either Quercus acutissima or Quercus variabilis
#2 Red Oak or maybe Black Oak, not certain which
#3 Looks like a Sumac of some kind to me, a Rhus variety
#4 Looks a lot like an Elderberry, a Sambucus of some kind
#5 Not at all sure on this one. I was thinking another Elderberry of Crepe Myrtle.
Don't know if that's helpful, but I hope so. Good luck!