The Public Record Office of Victoria (PROV) - http://prov.vic.gov.au/ - has shipping records for those coming and leaving Victoria until 1923.
In the records the name William has been recorded in many forms.
National Archives of Australia - http://naa.gov.au - holds records relating to migration after 1923.
To locate additional sites about shipping lists online a good place to start is CoraWeb -
Books include Charles Bateson, The convict ships 1787-1868.
Books have also been written about specific journeys - Sian Rees, The floating brothel (The Lady Juliana).
Websites about convict ships include:
Convict ships to Australia - http://members.iinet.net.au/~perthdps/convicts/ships.html
Irish convicts to New South Wales - http://members.pcug.org.au/~ppmay/ships.htm