Google has announced that its Google Scholar Citations application is now open to all: http://googlescholar.blogspot.com/2011/11/google-scholar-citations-open-to-all.html
In addition to automatically identifying your publications available via the Web (including Google Books), Google Scholar Citations allows you to customize your own database, adding conference papers or publications that might not be readily available otherwise.
Google Scholar Citations tracks who and how often your published work is cited. These data may be useful in your developing a research agenda.
You can choose to make your profile and citations index public (extending your international reach) or to keep it private.