One of the most difficult aspects of all for beginning students of Japanese is trying to learn how to read the Chinese kanji characters that make up a significant portion of the written language. That's because doing so requires that students be able to break down each character into its essential parts and then be able to use a special "character dictionary" to discover the meaning. It is a painstaking process for beginners -- one that would greatly be facilitated by having a good dictionary at their disposal. One of the best out there is The Original Modern Reader's Japanese-English Character Dictionary by Andrew N. Nelson.
At first glance, beginners might be intimidated by The Original Modern Reader's Japanese-English Character Dictionary because there doesn't seem to be any rhyme or reason to the entries. That's why -- unlike with dictionaries for languages using a familiar alphabet -- it's critical that would-be users read the instructions on how to use the book first. Strangely, the instructions come at the very back of the book in the Appendix section, rather than right at the front with the forward from the author. But I guess that's just a minor point that doesn't really matter in the end.
After reading the instructions, you will see that Nelson developed a whole system for breaking the kanji characters down into their most basic form, which is called a radical. Nelson's system is supposed to be one of the quickest ways for students of the Japanese language to identify radicals of kanji they've never seen before. I'm no expert, and all of my professors have followed the Nelson method, so I can't really compare it to other techniques to see if it really is faster or not. But this particular method involves 12 separate steps that basically have you looking at all different aspects of the character you are trying to find.
The process is quite complicated at first, because the order in which you identify the components of the kanji is extremely important. For example, Step 8 of the identification process would have you look at the northwest (NW) corner; Step 9 takes you to the NE; Step 10 would have you turn your attention to the SE corner; and Step 11 brings you to the SW corner. It takes lots of practice to be able to follow the 12 steps in the right order, but there are plenty of examples in the Appendix, so you'll likely be able to learn how to do it on your own. Once you know how to look up a character, it becomes almost second nature when using the dictionary.
In addition, there is also a "Sound Index" that you can use to find specific entries, but this requires that you already know how to pronounce the kanji that you are trying to look up. I've never used the Sound Index because I've found that usually when I have to look up a character, I don't know how to pronounce it anyway.
After you learn how to break down the characters into radicals, the dictionary layout makes much more sense. As for the definitions themselves, I've found that they are pretty sparse considering the size of the book. They are mostly just one-word synonyms, with no usage examples and no indication of what part of speech (noun, verb, adjective, etc.) the word is. You get the character compound, a "romanized" pronunciation entry, and then the definition itself. In all, there are something like 70,000 total entries in the dictionary, which should certainly be sufficient for most students, whether beginning or advanced.
Overall, I have to say that The Original Modern Reader's Japanese-English Character Dictionary is a very useful book for students at all levels of Japanese study. It has been around for a long time, so you'll probably find that many professors learned from this book themselves, and continue recommending it to their students. Its longevity shows that it's still relevant, so check it out today!