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Even outside the members-only programs, the FileMaker developer community is a congenial bunch. You'll find lots of resources on the Internet, including free newsgroups and websites. Many independent consultants' sites have free or low-cost resources, too, like lists of custom functions free for the taking or sample files that show specific techniques.
The most hands-on way to stay abreast of what's new with FileMaker is to join a local user group. There you'll meet other power users and developers. Meetings usually consist of a presentation and Q&A session. Presenters can be FileMaker staff or out-of-town developers. Some groups also sponsor day-long programming camps. Check out www.fmpug.com/filemaker_data.php to get the current list of local groups.