I've read threads about this part of the GMAT, but I haven't seen any addressing my question.

Are there any threads addressing what to do when you're not familiar with the topics you are required to write your essay about? What do you do then? Thank you.

First of all read this guide : how-to-get-6-0-awa-my-guide-64327.html
Having and following a template is half the battle.

In the analysis of the argument, you really don't need to know much about the topic in general. Your task is to write a critique of the argument. So its really an attack on the logic of the statements presented and how the conclusions are drawn and generally not the conclusion itself. Also you can always say things like not enough examples or enough data to corroborate the claims. By in large, having this template in mind a lot of the work is already done for you.

On the issue bit, it is a bit harder because you need to present a view. But then, you would not get any topics which will require you to be an expert on the topic at hand.

Also, you must note that the AWA topics come out of a finite and known pool of questions, so you can always go through them and give yourself a bit of confidence that it is unlikely to see a question that will leave you completely flumuxed.
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