hi! there's lots of room for more input on the various countries, but meanwhile you can get started on some previous discussions
Was South America involved in WWII to any significant degree?
Why did Brazil become involved in WWI and WWII?
There is a lot of material on US and Canada involvement in European theater in WWII. However, I can't recall roles other Western hemisphere countries played. Especially large ones such as Brazil, Argentina, Chile, Mexico, etc.
FAQ section Nazis in Argentina