Hi Simoned,
John's post is very helpful and some great advice.
Another way that many people "appear" to have online stores is by being affiliates of products.
This way you build a website and list other people's products, when people click through to those products to buy using the links on your website, you are paid a commission.
That way there is minimal cost involved, and no stock handling, there are many, many, many websites online that operate this way.
Take a look at
http://www.clixgalore.com.au or
http://www.commissionmonster.com they both offer Australian affiliate programs by some very reputable companies.
Hope that helps some,
Loreena