I have a hypothesis I'm trying to test, which is that ideas on the internet  are generally not very diverse. That is, even when there are opposing viewpoints, there are usually only a few views total on a given topic. So, I'm looking for **data sets cataloguing things like online newspaper articles based on the general ideas they present**. A hypothetical example would be a database on articles about the 2012 election campaign that catalogue them based on whether they mention abortion, gay rights, immigration, or job growth. In that case, I might be able to  demonstrate that the majority of election coverage centered on those topics, as demonstrated by the high frequency of those terms in online articles. 

Another example might be data from twitter or Facebook tagging posts by topic/key word. I could potentially demonstrate that social media activity is dominated by certain buzzwords.  I know that google has an n-gram search for books, but does anyone know of one for the internet or for newspapers?

There are plenty of other studies you could do; it doesn't matter much to me what the topic or specific material is. I also don't mind if it's a very small data pool. I'm just looking for data that would lend itself to a case study of trends in written information online. If anyone has any ideas, I would be indebted!