Juniper - I may have the answer to all your problems!

Firstly - yes, mainstream tanning creams are full of chemicals that you do not want circulating in your body.
Secondly (the good news) - A company in London called The Organic Pharmacy have pioneered the first ever toxin-free completely natural fake-tanning cream. It uses natural sugar beet to temporarily change the actual pigment of the skin, rather than dying it with toxic chemicals!! I bought a bottle of it when I was in London and it is the ultimate. Downside - its not cheap! Especially when you consider the ratio of pound to aussie dollar.
You can send an email to them on their website to find out cost including postage. They frequently send their products all over the world and they are GORGEOUS!!! They have a few select stockists in Australia that you may want to check out - should be on the website too.

Hope this helps. XX