Reading about social networks and opinion leaders

Thanks to Professor Longstaff, I've got an extensive reading list for this research study. In addition to what amounts to a small forest of journal articles (thanks to Dr. Liu), I'm reading a few books that discuss the nature of networks and opinion leaders:

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  Six Degrees: The Science of a Connected Age by Duncan J. Watts


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  The Tipping Point: How Little Things Can Make a Big Difference by Malcom Gladwell


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  Linked: How Everything Is Connected to Everything Else and What It Means by Albert-Lszl Barabsi


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  Bowling Alone: The Collapse and Revival of American Community by Robert D. Putnam


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  Better Together: Restoring the American Community by Robert D. Putnam

My study builds on the notion that online social networks are much like traditional social networks in that opinion leaders are critical to communicating an idea or introducing a product. This goes along with Everett Rogers' Diffusion of Innovations theory and Paul Lazarsfeld's Two-Step Flow of Communication theory, which I'll include in my literature review.

I'll be going straight to the original sources, but I've included links to Wikipedia as information. Incidentally, Diffusion of Innovations and Two-Step Flow of Communication could use some help on Wikipedia.  There's hardly anything written about either of them.