'Google Alerts' is a super way to build, maintain, and promote your knowledge base in your niche field. The alerts keep you abreast of what's happening in your field, and provide material to blog to others. The material can be
Reposted to Facebook or tweeted, Pinterested, etc., "as is", if it is of potential interest to your fans, but not sufficiently important for composition of a post on your blog
Reworked and reposted on your own blog, which can then be posted to FB, tweeted, etc., as appropriate to your readers. The advantage here is that the social media posts then link to your blog.
Consider creating a number of social media sites that emphasize different dimensions of your expertise, where you can post your material. These need not be product sites, but the material can ultimately link back to your main sales or information page.
Google alerts is here. I maintain a separate email account for 'news' items, dedicated to alerts and as a place to compile ideas for posts.
Do you have other suggestions that work for you? Please share!