Digital Librarians & Statisticians
I also came across this review of Internet metrics and statistics. Unfortunately, this piece is plagued with link rot, but the general overview (and clues about where to look for further info), is invaluable.
There's also this piece from folks at Stanford and Princeton about a method for random sampling the web by using a random-IP-number generator. Fascinating for thinking about a sociology of the web in general, if not imminently useful for looking at hate groups online.
More directly relevant for my work is an analysis like this one of Italian fascists on the web. I especially like the idea deployed here of using web links to do a kind of social network analysis.