The Text Prize is an annual prize (est. 2008) for unpublished manuscripts in the YA and Children's categories, and is opening on April 30 for submissions through to Friday, June 1, 2012:
Both published and unpublished writers of all ages are eligible to enter with works of fiction or non-fiction. Judged by a panel of editors from Text Publishing, the winner will receive a publishing contract with Text and a $10,000 advance against royalties.
Note this is for manuscripts of at least $25,000, for Australian and New Zealand permanent residents.
You can find the full submission details here: http://textpublishing.com.au/static/files/assets/7dd4cad5/TextPrizeEntryForm2012.pdf