You can add any python package hosted on git-hub by adding a search link URL pointing to the project url as well as a postfix #egg=packagename. For pyfacebook:
http://github.com/sciyoshi/pyfacebook/tarball/master
Thus, a simple layout would be:
[buildout]
parts = whatever
find-links =
http://github.com/sciyoshi/pyfacebook/tarball/master
eggs = pyfacebook
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