This areas needs checking all the time. I'm finding it hard to keep up with all the changes and gadgets available!
We found Exetel to be ok. Much cheaper than Bigpond. We get free voip service with good rates. All in all our internet 12gig peak and unlimited off peak: $45 + phone calls- usually $10 and homeline is $19.95. And no contracts.
Our mobiles are getting used more than they used to be so we have changed plans and they are prepaid. $30 every two months. This has heaps of freebies, SMS and chat time etc.
To find great discussions on Australian providers check out http://forums.whirlpool.net.au/
Very helpful stuff in there :o)