I thought it might be a garden orb spider but now Im not sure. Please help

I think you are right http://museumvictoria.com.au/spiders...spx?id=5&pic=0

Does it do a new web every night?

Thanks we were just confused by the red legs - thanks for the link very useful
Not sure about the new web we saw it for the first time last night - right in front of the front door - shes now hiding under the guttering and no sign of a web - At least we will be expecting it tonight!!

More certain it's an orb then as they re-do their web every night.

We've got a couple around our gazebo, one is huge!! Amazing to watch them doing their webs, they are so fast...!

Yep thats an orb weaver, they eat their webs usually every other night for a protein fix. They live for about 1 year. I've got a huge one in my back yard, its been in the same spot for about 2 months, webs there one day gone the next, with just the anchor strands of the web remaining. Great looking spider.

Got a couple in my garden too, they are pretty amazing, ours seem to do a new web everynight and like you say leave the anchor strands in place. I keep meaning to have a look before daylight to see if there already gone and what they catch.
I walked in the web one night when watering the plants, I was amazed how strong it was, I reckon a small bird would of got stuck in it!
I found the spider at the bottom of the pool the next day....

Never had them before and have lived in the house for over 4 years.

It'll tuck up in a crevice near where it makes it's web during the day. You can normally see them though as they don't go deep.