Australian:

G & M Cockatiels - http://www.powerup.com.au/~squawk

Information on Cockatiels - http://www.geocities.com/birdsofafeathermw

Australian Bird Clubs:

The Native Cockatiel Society of Australia - http://www.cockatiel.org.au

The Australian National Cockatiel Society - http://www.cockatielsociety.org.au

The Parrot Society of Australia - http://www.parrotsociety.org.au

Avicultural Society of Southern Tasmania - http://www.southcom.com.au/~birdkeepers

Overseas:

Elsie Burgin's Cockatiel Mutations - http://www.showbirds.com/tiels

Parrot-Link UK (hundreds of links to other bird related web sites) - http://www.parrot-link.co.uk/weblinks.htm

The Parrot Pages (Avian Link Center with over 1200 links) - http://www.parrotpages.com