There are no online directories dealing specifically with twins (that we know of) but these are the biggest general directories to help you find pregnancy and parenting information in Australia.

Essential baby 
Australia’s most active online parenting and family communities providing information and resources for conception, pregnancy, birth, parenting and beyond!  EB also hosts one of Australia’s largest women’s forums – between 650-900 online in regular daily periods. Well Worth a Visit!

Bubhub
Get on this comprehensive Australian pregnancy and parenting site pronto for info, advice, community forums, articles and so much more.

Babyology
'Modern finds for hip bubs and parents' is the concept behind this terrific site, which is one of our favourites. With products from around the globe, Babyology is perfect for those who appreciate the finer things in life.

Baby Universe
This fast growing directory has a terrific range of articles, business listings, shopping directory and a forum.