Ok this is mine method to get free and unique content for your website. First use social networks to share competition for job for writer in some local news portal or something...Do it from your fake FB, TW profiles etc... Tell them how much they will earn use something normal, and put on contact email for more info. When they contact you via e-mail, learn them how to write good text that are SEO friendly. Then send to all people different topic (from your niche). And say that is for contest and who write the best they will get a job. When they send to you content, wait about 7 days and answer that they didn't good enough for that job... I am sorry for my bad English, i hope you can understand.