We went to Bunnings and bought a fly/wasp catcher that was recommended to us.
It has caught plenty of large flies, not sure how many wasps or small flies. We have noticed that the wasps/flies are not as bad since we got it but that might be the weather.
My aunt who lives in the Mallee used the fly strips that you hang as their flies were so bad.

Netix: I never thought to google for a solution, might look at it when I have time.