I'm in the process of re-watching 'The Pacific'. Two of the major sources for the series are With the Old Breed: At Peleliu and Okinawa by Eugene Sledge; and Helmet for My Pillow by Robert Leckie. Are there any works by former Japanese military servicemen on their experiences during WWII? In particular accounts from ground forces?
There is an excellent compilation work by Kazuo Tamayama and John Nunneley called Tales by Japanese Soldiers which are a series of eyewitness accounts collected from everything from interviews to articles in post-war Japanese veteran papers. The scope of the book doesn't extend itself further than the experiences of Japanese soldiers (and sailors, pilots, support troops, nurses) in Burma between 1942 and 1945. It is absolutely invaluable in my opinion and gives us a perspective which is very rare from a campaign that is usually overshadowed by other campaigns.
"The world at war", a BBC documentary has interviews with Japanese soldiers. I found them to be quite interesting. Also, the series as a whole is incredible.