While ssb’s answer is absolutely sufficient, I want to point out—in addition—an English resource that some may not think of in these circumstances.
Of the three current, major kanji–English dictionaries (Nelson, Spahn–Hadamitzky and Halpern), Jack Halpern’s New Japanese–English Character Dictionary is actually rather well equipped with information suited for us beginners.
This is part of page 47 (and a small inset of page 46), covering about a fifth of the total entry for the kanji 作:

While the other kanji dictionaries in English cover more kanji and use a (slightly) more traditional radical look-up method, they come nowhere near the amount of semantic information Halpern covers in this dictionary. They each have their own strengths and weaknesses, and I would like to say that this is Halpern’s strength.
(The latest edition of this dictionary goes under the name The Kodansha Kanji Dictionary. And it seems to have been expanded by some 1,000 kanji entries, 5,000 senses and 7,000 compunds; as well as some further 1.000 synonym expositions and about 100 additional usage notes.)