There is a good interview with Anand Gopal on the Sources and Methods podcast. Well worth listening to for his comments on information gathering.

Alex and Matt are joined by writer, journalist and polymath Anand Gopal for our inaugural episode. He talks about writing books, reporting in Afghanistan, how he stays on top of the news from a variety of countries, why it's so important to learn languages and many other things.
Sources and Methods #1: Anand Gopal