Create a form then use this code. Remember that unless you are only getting text files, you will need to find a program that will take the dump file that is passed through the webserver and create another file type with it. Things like graphics need this. You can find them for free on the internet though. Just search around yahoo. I'm sure they'll have something.
<form method="post" action="someotherpage.html">
<input type="file" name="file">
<input type="Submit" Value="Submit">