AusBonsai

Hi All,
For the next month I am staying at my parents farm in the Hunter Valley, and can collect any plant I want.

The first I have found is this grouping of an unknown type of tree. There are 20+, all apparantly stunted thanks to cows (none over 30cm, many around 15cm). A few at least caught my eye (plus many more maybes): I have had no luck getting an ID on this plant, I am really hoping it is a native. Here is a closeup of a branch: So, since this is to be my first collection, I was hoping to get some of your professional opinions on the suitability of the plants pictured in becomming bonsai.
-Can anybody ID this plant for me?
-Do you like the shapes of the pictured plants, can you see them as bonsai?
-Can you recommend a collection process? (I plan to water them a lot, and give them some seasol over the next month. Then just dig out as much around each as I can before bare-rooting them to be shipped home. I'll do more research on the actual digging over the next month).

Expect to hear more from me as I find more possible digs.

Thanks for your time

All those pictured above are in areas where my Dad is going to slash them away, in order to maintain grazing land for cows.

Today I found tons of gum trees that should be saved, only photo'd one which may have acceptable low movement. Trunk about 4cm. Must look closer at the rest. I was trying to keep clear of wattles, but I quite liked this one. Sorry for the bad angle shot, but I needed a reference point so I can find him again. I think this is a Casuarina. Funky trunk, though probably not the best shape for bonsai. Nice and chunky though. Will probably leave him be as he's in a safe spot. Any opinions would be appreciated.
Cheers, Pat.