For Australian teachers:

Teachers.on.net

Australia teachers

Teacher Appointments

Infoxchange Australia

For Government schools: 

Teaching in Victoria 

Teaching in New South Wales

Teaching in the Northern Territory

Teaching in Queensland

Teaching in South Australia

Teaching in Western Australia

For Independent schools:Aboriginal Independent Community Schools (WA)

For Catholic schools:

Catholic Education Office (VIC)

Job search:

Career One

My career

Seek

Voluntary work:

Australian Volunteers International

Volunteering for International Development From Australia 

Australian Youth Ambassador for Development

Teaching overseas: 

Education news and job vacancies 

Hays Recruitment

Search associates

Select Education 

Teach in the UK:

ANZUK Teachers

Protocol

Sanza

Smart teachers

Teach London

Teach UK

Teaching in the Middle East:

http://www.bayt.com

Teaching ESL:

Dave's ESL cafe

TEFL.com