Although there's a lot more in-depth, actionable information out there, this blog post by Amy Hoy seems tailor-made to your question:
http://unicornfree.com/2013/how-do-you-create-a-product-peop...
http://unicornfree.com/2013/how-do-you-create-a-product-peop...
If not: I think you'll find find the HN community doesn't react well to either stealing content or complaining about the (quite reasonable, in this case) cost of people's products.