The book for you is Nazi Prisoners of War in America. I could only guess why you never read about them.

German PWs were shipped to Canada, later the US, to move them farther from the theatre of war and to not add feeding them to the logistics of feeding the civilians of the UK. Many were put into agricultural work, so they were helping to feed themselves.

One of the locals I recall was Camp Perry, traditionally the sight of the national shooting championships. There were 700 camps for some 425,000 PWs. (POW is a much later term. In fact, they had PW printed on the hip pockets of their trousers to distinguish them.)

They were all inland, away fron sensitive coastal cities and ports, or industrial areas. The labor unions hated their use in factories and mills.

The earlier they were captured, the more hardline Nazi they tended to stay. The Afrika Corps tried to keep everyone in the camps politically correct, and seemed to specialize in the "suicide" of those they deemed disloyal to the party. Anti-Nazis who survived wound up at Camp Ruston, LA, in order to separate them.

Look for the "Faustball tunnel" for their own Great Escape: 178' tunnel out of an Arizona camp. The couple of dozen headed for then-neutral Mexico.