Everything Works Together: Your Blog Is Your Sales Hub.
Let’s say you set up a Pinterest board for your publishing catalogue. Then what? Do you tweet and promote the board? No, you don’t – the board exists for people to discover your books. Get a widget for the board, and place the widget in your blog’s sidebar.
Yes, you need a blog. In addition to the Pinterest widgets, you can add Amazon widgets to your sidebar too.
Your blog has many uses. Primarily, its use is to prime your writing pump, so that you create more ebooks. Your blog also encourages readers to sign up to your mailing list, so that you have a way of contacting them again.