Found in 2 comments on Hacker News
Just a nitpick: The O'Reilly book title is actually _Learning GNU Emacs_. (http://oreilly.com/catalog/9780596006488/)
kirubakaran · 2008-09-14 · Original thread
This is a good starting point: Learning GNU Emacs http://oreilly.com/catalog/9781565921528/

This might ease some pains: http://steve.yegge.googlepages.com/effective-emacs

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