Here are some of my favorite Flute Making Links
Pete Kosel's Flutomat calculators for 6 and 8 hole flutes...
http://www.cwo.com/~ph_kosel/flutomat.html
http://www.cwo.com/~ph_kosel/Flutomat-8.html
you can calculate by inserting tonehole frequency as well as selecting a keynote. adjusting for bore diameter and embouchure size is also easy. If you have trouble or questions, post them in the "European Flutes" section.
The Musicians and Instrument Makers Forum is a great source for archived plans and measurements. It can be intimidating at first, but plow ahead! Here is the main site and a wonderful "Links Area" for Woodwind Builders...
http://www.mimf.com/
http://www.mimf.com/link.htm#flutes
The Chiff and Fipple Tin Whistle site (message boards). This site has a great deal of archived music, but it also has a lot of builders "tweaks and insight" for the Woodwind Maker. Information on the "Ducted Flue" voicing/embouchure is hard to find but this site has a large data base.
http://www.chiffandfipple.com
The Recorder Homepage is a massive information site, like the Musicians Forum. This wonderful site has most of the information on the "Ducted Flue" voicing and variations. Measurements are not readily available for free though. I hope the Simpleflutes Site can change that(?)
http://www.recorderhomepage.net/
The Japanese Flute site is listed in the MIMForum links above, but I thought it rated a dedicated link for "traditional" techniques and designs that are hard to find.
http://www.asahi-net.or.jp/~DL1S-YMGC/index-e.htm
The Ocarinaclub site has years of archived information for those who want to make vessel flutes and ceramic instruments. Just ask for help if you can't find the information. The Members are very helpful.
http://groups.yahoo.com/group/Ocarinaclub/messages
The Encyclopedia of Organ Stops site has a large collection of diagrams in the Illustration section that can give insight into the workings of Ducted Flue and Flute design acoustics. Here is the main site and the diagram link
http://www.organstops.org/
http://www.organstops.org/_apps/Illustrations.html
I have more, but will post these when we have a dedicated "Links" list page(?)