Not sure if there is a real easy way to automate downloading all of
them on the Apple II. You may be able to write a Spectrum script to
download them somehow, but I haven't explored Spectrum's scripting
abilities.
I wrote this quick BASH script under Linux. Change 9999 to the last
document you want to download. The documents may have some formatting
errors, but most should be readable. This will create files 9999 text
files, named #.txt in the current directory
i=1
while [ $i -le 9999 ]
do
lynx -center -dump http://docs.info.apple.com/article.html?artnum=$i
$i.txt
sleep 2
let i=i+1
done