Ellis Ashmead-Bartlett - The First Report in Australia of the Landing at Gallipoli (anzacsite.gov.au)
Note the further links at the right of that page.

 

Charles Bean - The First Report (anzacsite.gov.au)
Originally published in the Commonwealth of Australia Gazette, 17 May 1915.

Despatches from Gallipoli: The Correspondents (nla.gov.au)
Click on THE CORRESPONDENTS at the top or the links at the bottom of the screen for:
●  Charles Edwin Woodrow Bean
●  Commonwealth Gazette
●  Sir Keith Murdoch (View the Gallipoli Letter manuscript. For a recent newspaper article about a book based on the letter, see Book review: The Gallipoli Letter, nzherald.co.nz. See also our Issues page: Gallipoli, Sir Keith Murdoch and WikiLeaks.)
●  Ellis Ashmead-Bartlett
●  Phillip Schuler and Charles Patrick Smith

Despatches from Gallipoli: Censorship (nla.gov.au)
●  An example of censorship
●  Diaries versus despatches

Kitchener's & Hamilton's Reports on Gallipoli (lib.byu.edu)
9 August 1915.

See also:
Australia and World War One: Documents (exetel.com.au/eduweb)
A variety of documents from and about World War 1.

Some other sources:

● Anzac diaries

● Anzac biographies

● Anzac letters

● Anzac interviews

● Gallipoli Campaign