You won't need to purchase any software.
The first thing you want to do is check what your web-server offers, for scripting. (perl, php, cgi, FrontPage extensions, etc)
Then, find an upload script for what you can use. Tonnes of them available for free.
If you can use php, I'll email you a template for an upload script.
(Oh, and you should check out the options under "forms" in your Front Office. Not familiar with that one. It may have templates built in.