Wwoofer are Willing workers on organic farms. Although the only requirement for someone who offers you a position is farm work, which might even be an extended vegetable patch.
Wwoorfer will work in exchange for room and board. If you are interested in finding a place you might want to check out the Harvesttrail website from the Australian government.
You can search for jobs by postcode, which is just great if you look to get your 2nd Working Holiday Visa, as Wwoofing will be recognised for it, as long as your employer aims to make a profit.
You will also find quite a bit of information on the internet where other travellers share their information and rate the work conditions.
Important: If an offer is too good to be true or you are required to pay any money in advance it probably is a scam.
Wwoofing is also great for AuPairs who have a little down time, eg. the host family is away on holidays. That way you can really experience the Australian country life.
You can also go wwoofing with a tourist visa under certain conditions, which is mainly being a genuine volunteer.
- work as a genuine unpaid volunteer,
- but only if an Australian resident would not otherwise be paid to do the work
Note: You can be reimbursed for out-of-pocket expenses such as meals and accommodation.
You can read up at "What this Visa lets you do", then go to "Tourist Stream": http://www.immi.gov.au/visas/visitor/600/holders.htm
If you really do not like farm work at all, but you would love to do something different except being an AuPair and travelling, you should consider to volunteer.
All of the big job search engines in Australia will have their own tab for it. Just have a look, you never know what you will find ... maybe you can help out in the koala park.
This is just a short information so that you simply keep your eyes open to see what Australia has on offer for you. You can make a wealth of experiences.
Just grab them!