Writing on a blog nobody reads isn't going to do much for you. The way content gets backlinks typically involves the people who write it hustling just as much to get those links: posting them themsleves, talking to influential people who can share them, running contests and giveaways, guest posting for exposure. Content creation is less than half of the work of successfully using content marketing for customer acquisition.
You can't really outsource this stuff at the beginning IMO. Nobody else is going to have the knowledge and the passion to get those early customers for you. You need to be in the loop personally to hear the rejections and see how your product is being used to know how to move it forward and how to market it more effectively.