As someone who records a lot of different amateur voice people daily for language courses, I'd have to disagree with some of this.
It's generally an OK guide, but I would suggest the mic recommendations are incorrect. I'd like to see an AT2020 USB in the mid-range and Heil PR-40 on the higher end. It's cheaper and significantly better sound. I own the H4N for mobile recording, but the quality really doesn't come close to a proper broadcast mic like Shure SM7B or the Heil. You can hear the Heil from a lot of pro podcasters and the SM7B on Marc Maron's WTF and a lot of radio hosts.
It also glosses over the use of mic arms, pop filters in getting pro sound. It's geared towards on-the-go recording and the quality will be nothing like a studio result.