I know some folks who have some elaborate arrangements set up for tracking stuff across a variety of blog search engines. And catch lots of interesting things. Most folks I know probably never use any of them.
As Steve Lawson points out various folks have ego-feeds to allow them track mentions of theirs truly (I am sure he will see this in his own ego-feed ;-).
I have a variety of watchlists and equivalents set up. Some relate to aspects of work (not many), some to other interests (not many) and, OK, there are a few ego-feeds (not many). This last is partly out of a natural curiousity, and partly because it is a good way to track the currency and coverage of the blog search engines.
Recently, my impressionistic judgement is that the relatively new service from Ask.com/Bloglines gives the best overall results, ahead of blogsearch.google and Technorati or Feedster. These are the services I tend to look at.
However, I have just come across www.sphere.com which appears quite nice, and I will try it for a while. Try a search, and it gives you the option to ripple it through to a search of books/photos/podcasts (apparently based on Yahoo! and Amazon).
I will try this for a while and see how it does.
I came across it as it is used by the interesting FireFox extension BumbleSearch.