This page has a lot on it. You can use the following anchors (links down the page) to jump straight to a relevant box.
Base search for ego documents in a library catalog can include (memoir OR diary OR letters OR "personal narrative" OR autobiography) AND whatever topic you're looking for. Here is a base search for material with "Korea*" as a Subject. I suggest limiting the memoir, etc., to a title search for more precise results.
See also section "U.S. and Britain on Korea" below.