Here is a collection of FFT programs that appeared in
S.Mitra&J.Kaiser:
Handbook in Digital Signal Processing, John Wiley & Sons,
1993, ISBN 0-471-61995-7.
thanks to Henrik Sorensen for the code !
thanks to John W. Herman for the pointer to Henrik Sorensen :)
this is also avialable at
ftp://ftp.teleos.com/VISION-LIST-ARCHIVE/SHAREWARE/CODE/FFT/FFT.shar