Firstly how bigs the boat???? Id suggest out to the 90's but if its a tinnie you got no hope. So more info would help. Also fill out your profile!!!!!!

It does help us willing to help build up a mental picture. To get a few fishing spot does take some time and patience, ie some hard and expensive work to get the spots, so dont find it offensive when people will only give you a general idea about where to go. But you wont get a GPS spot of someones worked for location. Its not considered polite to ask for fishing spots, but I am sure on here you will get directions to start areas, and then work from there.

Any of the areas you mention above is a good start. Look for reefy ground with adjacent sand IMO. Back of GI is also good from reports but I personally have never fished there in a boat. In Perth fished north of carnac and south of Cott. Draw a line directly out from there and thats the strip I fished.

Mandurah was home and has some great reef systems not very far out. I generally dont fish in depths that will tire the arms pulling a large sinkers, but prefer 30-50m when chasing Dhu's etc, and shallower for KGs, say 10-20m. Basically I keep the plans simple, and these 2 are my targets down there.

So sound around a reef in the depth you like, anchor or drift whichever you prefer, and good luck.

It is poor form if you "ping" another boat, so stay away from other boats because its a big ocean, with lots of spots to be found. Its a sinking feeling when you go out to a favourite spot, find someone has it as theirs aswell, and got there before you. Just go to the next.

There is exeptions to the dont go near other boats suggestion, like snapper fishing in the Sound, when there may well be boats parked right next to you, and also salmon at Rotto's West end, when people use each other to track the schools down, and then want everyone around to "fire" them up.

So build up the profile, with some details off the gear you have, boat etc.

Up here in karratha the advise was very much the same, like go to the Inner or Outer Patch, the pipe line etc, but the rest you have to work at. Soon enough you have your own spots to be proud off.

Cheers and good luck

Neels