When you are looking to register a domain name in the Australian name space it's always best to use an auDA accredited registrar. Cheaper domains, an accredited registrar, can provide you with detailed information on who owns a domain name or if a domain name is available to register. This information is provided for .com.au, .net.au, .org.au, .id.au and .asn.au (and, perhaps in the future, .info.au).