Thankyou to Snail for the advice on my question of whether the insect I saw last weekend in my vegie patch was a native Australian bee. Seems it is not a bee but a hoverfly
The excellent Australian Museum Online shows my hover fly – it seems they are often mistaken for bees and wasps.
They are also predatory feeding on things like aphids – so will definitely be encouraging them in this garden.
There is also some great information on a blog I recently found about Brisbane Insects.
Wildflowerings - Art Studio Diary 
I found your site on technorati and read a few of your other posts. Keep up the good work. I just added your RSS feed to my Google News Reader. Looking forward to reading more from you down the road!
Your blog is interesting!
Keep up the good work!