I have run across a few useful resources for network analysis recently, including:

• Mini-Course on Networks: Howard Rheingold has put together a very nice mini-course on networks and network analysis. It includes two videos where he describes the history of networks and some of the basic concepts of network analysis, links to other videos, a good bibliography for network analysis, and links to other network resources.
• Measuring Online Influence: A post by Allison Fine looking at ways that we can measure influence online – she incorporates some ideas from Valdis Krebs, the key one being that it is not simply our direct connections that are important, but the indirect ones.
• Networks, Crowds and Markets: The upcoming book by David Easley and Jon Kleinberg is available for free download as a pre-publication draft. Here is how they describe it:
  

  Over the past decade there has been a growing public fascination with the complex “connectedness” of modern society. This connectedness is found in many incarnations: in the rapid growth of the Internet and the Web, in the ease with which global communication now takes place, and in the ability of news and information as well as epidemics and financial crises to spread around the world with surprising speed and intensity. These are phenomena that involve networks, incentives, and the aggregate behavior of groups of people; they are based on the links that connect us and the ways in which each of our decisions can have subtle consequences for the outcomes of everyone else.

  Networks, Crowds, and Markets combines different scientific perspectives in its approach to understanding networks and behavior. Drawing on ideas from economics, sociology, computing and information science, and applied mathematics, it describes the emerging field of study that is growing at the interface of all these areas, addressing fundamental questions about how the social, economic, and technological worlds are connected.

  It looks like a terrific resource from two of the best network researchers around. (thanks to Michael Martin for the pointer)

If you want to learn more about the importance of networks and how network analysis works, this is a great set of resources to start with!