Hanja are arranged in the seven levels of the 한국어능력시험. If you don't know what that is, it's the hanja test which koreans themselves take. After elementary school they are at about level 5; level 8 is the easiest, it's first grade stuff over here. Level 7 is like 2nd grade material. Level 1 is pretty near impossible for a foreigner, and even also for koreans. (I know a Korean woman who majored in korean in college but only passed level 2, and was proud of it.)

Structure is PURE KOREAN + 을 + HANJA READING (hanja pronunciation written in hangul). Sometimes there is JUST WORD WITH KNOWN MEANING (usually PURE HANJA word) + HANJA READING (sound in hangul)