In the Book "Out of Nowhere" I found a story about an unnamed American who was traveling in Africa and ended up being recruited by either the CIA or possibly the South Africans to kill Russian advisors in the Angolan war of Independence. I was hoping to learn more about mercenaries operating in Africa during the last century and learn more about what happened in Angola during this period. Does anybody know any good books about these subjects?
Is there anything specific you'd like to know? Because it seems like you have two questions: one concerning mercenaries in Africa (which is honestly a history covering most of the Cold War and which, at the lack of proper sources, be shallow at best) and one regarding the Angolan War of Independence which lasted between 1961 and 1974. The person mentioned in Out of Nowhere did not claim to fight in the Angolan War of Independence but rather in the Angolan Civil War (1975 - 2002).
I've also come across that story and I always found it rather dubious. The only source is the interview that this individual had with Martin Pegler and Mr. Pegler, who is a talented firearms historian, only uses him as an anonymous source without any corroboration beyond that.