My startup just launched a blog, and I am trying to build an audience. What distribution tactics will be effective?
Renee's answer is spot on. Trying to guest blog on places that already have traffic will help. Often times you can link back to other blog posts/content you've created if relevant to the article.
The biggest tip is to see content as a framework for many types of deliverables. For example, recently we created an ebook called "Don't Leak Leads: How To Identify Leaks & Get More Customers". http://go.reachlocal.com/DontLeakLeads_request.html.
This content became a series of blog posts, a successful webinar series, multiple infographics, slideshare presentations, and videos. Because we focus so much on education, we also created http://dontleakleads.com. Again all of this was repackaging and rethinking a content framework around how to get more leads.
From a channel perspective, this gave us content across FB, Twitter, LinkedIn, Slideshare, YouTube, and Pinterest and for social media ads, updates, and even pinterest.
Then leveraging a content calendar you can plan when all this happens. Our entire goal is to get someone to fill out a lead form that enters folks into a 21 email behaviorally driven lead nurturing program.
I recommend reading Content Marketing Institute and CopyBlogger.com.
Best of luck!