There are a number of websites where you can find information on Commonwealth and State legislation relevant to the Royal Commission.

Commonwealth

Royal Commissions Act 1902 (CTH)
Royal Commissions Regulations 2001 (CTH)

New South Wales

Royal Commissions Act 1923 (NSW)

Victoria

Evidence (Miscellaneous Provisions) Act 1958 (VIC)

Queensland

Commissions of Inquiry Act 1950 (QLD)

Western Australia

Royal Commissions Act 1968 (WA)

South Australia

Royal Commissions Act 1917 (SA)

Tasmania

Commission of Inquiry Act 1995 (TAS)