Below are some links to organisations you might find useful. If you know of other links that should be included here, please let me know by emailing me at email@example.com.
Recorders and Early Music Union, based in Wellington.
Society of Recorder Players. A UK organisation but the website has some useful information about playing the recorder, especially the section "The Recorder".
Recorder Home Page. An amazing site compiled by Nicholas S Lander of Tasmania that has an enormous amount of useful and authoritative information about all aspects of the recorder.
Antique Sound World Workshop. Based in the USA, this site has a lot of useful information in their Information Bulletins section.
Orpheus Music. This is a wonderful recorder shop based in Armidale, New South Wales. They have a huge stock of music to buy, with quick delivery, plus some downloadable music. They also run a great one-week residential course every January.
Moeck. The English-language site for Moeck, useful for the section "Practical and worthwhile tips for recorder players" in the "Recorders" section.
Mollenhauer. The English-language site for Mollenhauer, useful for the FAQ section.
Kung. The English-language site for Kung.
Team Recorder - a YouTube series of tutorials and more by Sarah Jeffery - highly recommended