Twitter - follow edutopia, huffington post education, news or media outlets you already read, educ journals in your content or level, Diane ravitch, will Richardson, Heidi Hayes Jacobs, edsocialmedia, etc
Blogs - there are about a million (+) but you can check out one and usually they link to other bloggers they like. Start with
timbedley.com or
angelamaiers.com or Classroom 2.0 or dangerously irrelevant