I have long wished to be able to purchase Kindle versions of the old Bantam War Series of books about WWII by the publisher Bantam. It appears that I am finally getting my wish as I recently found two small publishers (The P-47 Press and Bowsprit Books) that appear to have most of them. The best part almost all of the ones I have looked at are around .99 cents with others that go up to around 2.99. I'm posting links to three of them but if you follow the also bought links you will find most of them.
Hellcats of the Navy
https://www.amazon.com/Hellcats-Sea-...9G9CTP17YC0QGQ
Author Charles Lockwood (Sink ‘Em All) brings his unique flair for submarine warfare story-telling to his account of Operation Barney, the secret mission during World War 2 to extend the conflict in the Pacific beyond the Sea of Japan and closer to the enemy’s coastline. (the picture on the cover of this is in direct conflict with what is inside. It is about submarine operations not the F6F Hellcat divebomber.)
The Far Shore By Edward Ellsberg
https://www.amazon.com/Far-Shore-Ann...PVES1J91QJ0P4D
Edward Ellsberg's The Far Shore is the riveting first-hand account of the Allied D-Day landings in France in June 1944. A principal actor in the invasion, Ellsberg describes in detail the massive preparations for the launch of the greatest armada in history. He devotes the second half of his book to an unforgettable real-time account of the bloody D-Day landings
US Military in WW2: The Submarines (Annotated): Rendezvous By Submarine, U.S.S. Seawolf: Submarine Raider of the Pacific and Sink 'Em All
https://www.amazon.com/Military-WW2-...1XFW67RM76H2SP
US Military in WW2: The Submarines presents three classic first-hand accounts of life aboard a US Navy submarine during World War 2.
(I've read all three of these and the third one "Sink Them All" is the best of the three, but they are all worth reading.)