There is not Australian Embassy in Tanzania however there is a Honorary Consul in the country. You can find the contact details for the Honorary Consulate in Tanzania listed below. If you want to apply for an Australian visa then you will note that this gets done at the Australian High Commission in Kenya.
If you want more information about Australian visas and the application process then you can search this website for more information. See also the contact details for the High Commission in Kenya on this website.
Australian Honorary Consulate in Tanzania
Address: Plot No. 431, Mahando Street, Msasani Peninsular, Dar es Salaam, Tanzania
Telephone: (+255 22) 260 2584
Facsimile: (+255 22) 260 1809