Wget.
I thought you did not like wget.
Regardless of whether he likes
it or not, since you have to get past
the initial form where you
type your search query, there is
no simple way to download
their whole database.
I believe that they used to make
some CDs available (presumably for a fee).
It might be easier to get hold
of those (assuming the old scanned manuals
and datasheets are on there!).
Antonio