Texts in various languages can be found
on the Gutenberg Project Catalogue. Just copy some html link (a text link is also ok but not a zip file) of your interest, paste it below and submit. To see how it will look to the analyser, you choose "Preview text": always check! Texts may contain non textual elements that leave parasitic combinations when deleted; moreover, if the encoding of an html file is not announced in its header, the conversion to utf-8 will not be performed by lynx; finally, for .txt files, if the encoding is not utf-8, the output will not good. Books in French edited at Athena are usually clean (but there may be one file per chapter).
Of course, you may use your own text, provided it can be accessed from the internet.
On a PC, if you save the statistics as a text file, you can then open it with Excel in utf-8 mode and use the data for further statistical processing. Unfortunately, on the Mac, Excel does not seem to be able to import UTF-8 text files.
Michel Boyer, 2009