You can do a quick search for lost or ATO-held super or create a myGov account and link the ATO for a broader view of your super. The ATO database holds information about active super accounts held by most super funds in Australia as well as lost and unclaimed super held by the ATO.
This is the Australian Securities and Investment Commission’s (ASIC) database for money that has been classified as unclaimed from banks, building societies, credit union, life companies, friendly societies and registered Australian companies.
A company must send unclaimed monies to the State or Territory they are located in. This may be different to the State or Territory you live in. They may hold unclaimed super from private sector super funds where the super became 'unclaimed' before 1 July 2007.