I subscribe to the Government Publishing Office (GPO) emails to get info on the books that they are featuring - every now and then they are WWII ones. Today's email was about engineer books since it is - apparently - Engineer Week. Who knew? Apparently, it coincides with the week of George Washington's birthday. This year it is February 19-25. The email I got sent me to "Government Book Talk" for Engineer Week.
As for the GPO, they are the place you can buy your brand new versions of the US Army's Green Books about WWII. For Christmas, I bought the Okinawa green book (with a picture on the cover and no longer green), some posters and a few small publications. Very cool. Anyway, it's pretty easy to navigate around the book store site. The search is ok but you will get a lot of results that don't have anything to do with your search parameters. Here is a search for "Engineers World War II"
https://bookstore.gpo.gov/search/apachesolr_search/engineer world war ii
Great place for government published books that are hard to get elsewhere.
Looking for the Green Books on PDF. . . and for free?
http://www.history.army.mil/html/bookshelves/collect/usaww2.html