Comet C/2012 S1 ISON is confirmed to be in outburst. The most recent magnitude estimates put it around magnitude 5.5, just above unaided eye visibility in dark sky sites. For most of Australia though the comet is so low to the horizon that you will still need at least binoculars to see it.
Comet C/2013 R1 Lovejoy is still bright and is currently around magnitude 5.6. It is higher above the horizon than ISON, but will only really be an unaided eye object in the norther part of Australia under dark skies. It is a nice fuzzy ball in 10x50 binoculars just under the sickle of Leo.
Comet C/2013 V3 Nevski should be magnitude 15, but has been reported as being magnitude 9, up from magnitude 10 of a few days ago. This makes it a telescope target, but it is reasonably high in the sky entering Leo.
All three are morning objects. Lovejoy and Nevin are best seen an hour and a half before sunrise, ISON, for all those south of around Cairns, is best seen an hour before sunrise (at the lattitude of Cairns and higher you can still see it an hour and a half before sunrise.