Other resources: The "Inform 6 and 7 Development" board at intfiction.org/forum is a great place to receive friendly and often very quick answers to your code questions, and there are other boards for talking about game design and playing existing games.
This forum post has a list of places to find Inform 7 documentation for a variety of tastes: http://www.intfiction.org/forum/viewtopic.php?f=7&t=3988
Among which I find these particularly helpful: Inform 7 for Programmers by Ron Newcomb: http://www.plover.net/~pscion/Inform%207%20for%20Programmers.pdf
Aaron Reed's textbook on I7: http://inform7.textories.com/
Oliver Reiser's I7 cheatsheet: http://user.cs.tu-berlin.de/~moreiser/inform/Inform7_CheatSheet.pdf
Emily Short's rules flowchart: http://inform7.com/learn/documents/Rules%20Chart.pdf
Note that the version of Inform we're using today is the latest release and the community is used to a leisurely pace between releases. Some of the above links may contain out-of-date information.
Juhana Leinonen released the full source for his Speed IF game Sparkle, written in the latest version of Inform 7, and with an index pointing out the places he uses various language features: http://nitku.net/if/sparkle/source_index.html