While searching http://mathforum.org/, which describes it self as "... a 
research and educational enterprise of the Drexel School of Education", 
I found the following
"
Browse and Search the Library
Home : Math Topics : Analysis : Fourier/Wavelets
"
http://mathforum.org/library/topics/fourier/

Their site map map also be of interest.
http://mathforum.org/library/toc.html