For Global at least, evaluate means that you have to make a judgement. It doesn't really matter what your judgement is, but there needs to be a statement that includes "successful", "unsuccessful", "relatively successful", "mixed success", or something along those lines. YOu also need to back it up obviously with evidence and for an 8-mark question (which are often evaluate) you probably need to make a least two separate points to support your argument/use several types of example. So for example, in AOS2, if you wanted to evaluate the success of a state in achieving its national interest, you would need to examine several different types of power/foreign policy instruments and how the state has used them as well as providing ways they have and haven't been effective (ie. discuss both success and failure).
Wow, Noam Chomsky... You might want to read something to balance out his views LOL. To be honest reading books for GP is not essential; you'd be better to read The Economist. Guaranteed to be something useful in every issue as well as lots of interesting IR stuff. Foreign Policy and Foreign Affairs are also good magazines as well for politics and international relations in general.