Here is a little beast I have been working on for some time. http://hollowbamboo.herobo.com/FDS/THC3.zip
It is pretty much a very flexible flute design spreadsheet for excell that allows you to design your own flute with the parameters that you enter. Unlike programs alike that I have seen on the net, this one does not create a virtual flute for you. It has that feature in it as well, but it has been made optional.
Pretty much I think I have included everything that a flute maker may need (and even more) to design a transverse flute. Tone Hole Locator, Bore Diameter Calculator, Options for Different Tunings, etc...
One of its main features is that it lets you input the length of your premade flute blank, and calculates all the other values according to it. Meaning that the final calculations are based on real thing, the flute that you are making, not a virtual flute.
I've tried it on several of the flutes that I made a while ago, and it works perfectly.
Take a look and tell me what you think. Comments would be appreciated. I did my best to outline instructions, but something that is less obvious to me may be not so obvious to others. Also, if there are any problems with the calculations or maybe I omitted some features that could be helpful just drop me a line. My email is on the website.
I hope that this spreadsheet will serve others just as good as it servers me.