@ Fiorite- Diving for lobster is tons of fun. I just look for reefs and areas where the lava flow has run of into the ocean forming porous cliffs and sheer faces. I do not know what kind of rock they have in Aussie, but I am sure you could find some hiding in the reefs out there.
Catching them during the day is easy because they are nocturnal. When they are in their hole, they are sleeping or resting. They also only have one way out, and that is right into your hands. Just wear gloves so the lobster or rock does not cut you up.