Social Media Examiner is "Your Guide to the Social Media Jungle."
A personal favorite of ours. With regular contributors, if you have any questions regarding social media they most likely have a detailed solution for how you should go about growing your audience and connect with them across different social media outlets.
Here are a few of our favorite articles:
The Social Media Examiner 2013 Industry Report
Social Media Marketing Trends
The Top 10 Ways to Improve your Social Media Marketing