I would agree with henry crun - 'A Bastard of a Place' is a far superior book to Peter Fitzsimon's 'Kokoda'.
Another book about the Kokoda campaign by the same author (Peter Brune) that I'd highly recommend is 'We Band of Brothers, the biography of Ralph Honner'.
Honner was the Australian commander at the Battle of Isurava, the single battle which, although the Australian militamen lost, in that they retreated from the field after the battle, probably did more the blunt the Japanese advance along the Kokoda Track than any other.
Damian Parer's iconic photograph of Honner addressing his troops immediately after the battle would probably be familiar to most Australians, and the speech he gave to them was more or less a 20th century St Crispian Day's Speech from 'Henry the Fifth'.
Both books deal with the fighting around Buna and Gona immediately after the Kokoda battles, involving (and killing off the majority of) the same Australian troops who fought on the Kokoda Track. The fighting at Buna and Gona was probably among the most savage one-on-one fighting that went on in WW2, right up there with Stalingrad. (Read about those battles and see if you'd agree with Max Hastings' assessment that the Australians bludged their way through WW2.)
You might not enjoy reading about those battles if you're an American. Neither MacArthur nor the American troops who were involved come out of it looking very good, and neither do most of the Australian senior officers, who, trying to please MacArthur (who repeatedly announced victory in the New Guinea campaign prematurely) tried to dictate the terms of the battle with little or no idea of the appalling conditions the troops were fighting in.
The battalion officers on site eventually won the day by ignoring the attack plans issued from afar and using the novel ploy of walking their troops into their own artillery barrage so as to have their men inside the Japanese trenches before the defenders emerged from their bunkers after the arty barrage stopped.