Does your web host support server-side scripting languages?
Do you know which ones?
I would run a search either on the PHP forum (if your host supports PHP) or the ASP forum (if you're hosting on a Windows platform instead of Linux of Unix) for a form sender and a file uploader example...
Otherwise, run some searches on Hotscripts (link in sig) once you determine what kind of server-side scripting capabilities your web host supports.