This book is the greatest thing since sliced bread, but I need more technical detail on a specific topic and/or long listings of sample code.
Facebook Platform launched with some official documentation (see http://developers.facebook.com, not to be confused with http://www.facebook.com/developers, which is the Developer app), but that quickly became out-of-date. Realizing that there was a veritable army of people who were happy to help keep the docs relevant, the Facebook team quickly launched a wiki and stopped updating the old docs, which languish as a reminder of days gone by. If you’re looking for info or want to contribute to keeping it real, check out the Developers Wiki at http://wiki.developers.facebook.com.
The Wiki is a real treasure trove of information but can be very difficult to navigate. Since it’s essentially crowdsourced documentation, different authors have come up with very different ways to organize different sections, which leads to a palpable sense of disorientation (as an example, check out the excellent index page for the FBML section and the chaotic jumble of FBJS’s single page). The joy of wikis is that we’re all free to update and edit them, and so I encourage you to contribute back to the community by jumping in and helping to keep it orderly, up-to-date, and well-organized.