I have just been stung to the tune of £3,600 (US$ 5,700) by the charlatan Ben Nickintz who runs a tour company called Niugini Eco Tours. He cancelled the tour 3 hours before I was due to start the 2 week tour and has never refunded the money. he apparently is renowned for doing this by either stealing the whole money, or providing a tour that is significantly below par in terms of sites and activities vs. the itinerary, or by requiring further funds during the tour due to "unforeseen circumstances" or by not providing food and accommodation for his guides making the clients feel guilty and pay for them.
I learnt all of this for the Tourism Industry Association of PNG who have black-listed him. Note that his website looks very professional but he does tend to change the name every year. Previously the company was called LET PNG (Life Experience Tours PNG). To ensure you don't get conned like I did I'd recommend that you only book with members of the Tourism Industry Association. Additionally I'd recommend you pay with a credit card so you can potentially get some compensation that way. I didn't and my World Nomads travel insurance won't cover it.
The country has so much to offer tourists. It's such a shame that cowboys like Ben Nickintz further the conception in tourists' minds that PNG is a place better avoided.