good luck trying to wake up!!!
it's freaking cold there now....well usually the 3 sisters site should provide a good one. The rest I can think of you have to hike up and down..not recommended if you didn't do bushwalking before.
For the usual/normal perspective (ie. the kind you usually see in calendars), just go to the lookout point for tourists. cant remember the name now, duh.:cry:
anyway, try going there one hour before sunrise. cold but worth the shot. i treasure the shot i did on this site many years back. remembered staying at the katoomba station backpackers joint, walked a few kilometers in the morning and probably burnt a full roll of film to get the one shot that i really liked.
had a 28mm lens back then. think if you have 20mm or even fisheye, it would give your shot a dramatic twist. and don't forget your tripod!
as an alternative location, you can do a bushwalk to the bottom of the three sisters and shoot upwards. not sure if you can do so before sunrise (check with the rangers) but you may want to try for sunset then!
long-winded post, but i hope it's helpful. cheers mate!