Where have there been any UFO sightings or close encounters in Australia?Yes - in fact, I've seen one. IIRC sightings are rarer than overseas though; probably because less air traffic means fewer blimps etc being reported.
They're pretty much the same as overseas. You are more likely to report seeing a UFO if:
1) you are within 10 miles of a military base,
2) directly before or after a thunderstorm, and/or
3) your name in some way indicates a fae or other magical background (frex lafayette).
After the cold war ended our militaries admitted to faking UFO sightings to make it harder to spy on their test flights, so (1) is less likely now.
A specifically Australian UFO are the "Min-Min Lights". These lights, loudly proclaimed as an ancient Aboriginal legend, are caused by a mirage effect that cause car headlights to be visible up to 50 miles away. By all accounts, very impressive.
You should check out the Westall UFO encounter.
UFOs have been reported from all Earth countries.
A cute Australian case would be the fredric valentich case. I may have the spelling wrong but it's an easy find. There are transcripts from a radio tower to his airplane during the incident. They read like part of a steven king novel!
And poor valentich was never seen again.