The ABCB manages the national construction code which includes the energy efficiency requirements for residential and commercial construction.
ACTPLA accredits energy assessors for work in the ACT. The list of current assessors is found here.
E3 covers the energy rating of appliances. The site includes a comprehensive product database showing the energy star rating of electrical appliances.
WERS rates the energy impact of windows in housing across Australia. The site includes a database with the specifications of residential and commercial windows.