Most of the guides you'll find suggest you build a profitable mailing list, but then go on to detail methods for doing so with a blog or website. Sure, if you have one it's great to know these things. But what really matters is driving traffic to that squeeze page and learning how to monetize your niche.
If you're going to purchase any information products that help you make money on the web, focus on those that help you convert prospects into subscribers and then selling to your list.
It's All a Numbers Game
With enough traffic, you can make money writing on just about any topic. There are people who have monetized the model railroad niche with hobbyist forums. A pizza delivery guy started a forum and created an ebook to teach other delivery guys how to stay safe and earn more in tips. These are extreme examples of niche interests, but the same lesson can be learned from each.
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