you can put an pdf form online for users to fill out and print, but unless they have the professional version of acrobat reader, they will not be able to save any copies of said form.
as an alternative you could use a regular html based form and have it submit to a script (php or asp for example) that will convert the content of the form to a pdf document. it would most likely require some modification, but you could then have a script automatically send you a copy of this pdf file.
you might want to give
www.hotscripts.com a visit. they might have something in their directory that would suite your needs.