Hi Mark,
I think there is some confusion as to what a 'form' is vs. what a 'document' or a 'file' is. A form is a web page that has textboxes, checkboxes, dropdowns, etc. that a person fills out and submits. That data is then emailed to someone.
A .pdf, .doc, .xls, etc. are 'files' that you can upload and make links to for people to download. You can create a form 'document' that has to be printed out and then filled out manually and mailed/faxed back to you. But that is still nothing more than a file or a document.