rry2k,
First of all, the online form is a means of gathering data to be shipped to a document? Question: Do you want to fax the web page or the document that holds the data?
Do you have fax servers available for your client that can process via "Web Faxing"? There several ways to convert web pages or the document. In other words, there are many ways to do this. It all depends on what your source is and what is available on the client.
I administer fax servers for my company.
fengshui_1998