Best Lancaster ops book: "The Eighth Passenger" Miles Tripp, flying No.218 Squadron Lancs out of Chedburgh and post war crew reunion and thoughts of the bombing campaign. Look for the revised copy.
Best B-17 ops book : "Dead Engine Kids" John J Briol, diary of ops flown from 457thBG Glatton,UK. Hard to find and expensive but a good read.
"Serenade To The Big Bird" by Bert Stiles flying B-17's from Bassingbourn is a classic on the strain of operational flying.