If you just want people to download a file for free and don't need to collect a name or email, and if you don't need to issue each person a unique link that expires, then you can just upload the file to your Web site and make a link to it, just like you'd make a link from one page to another.
If you do want people to get unique links, then you can use our Send Free Links feature or our Newsletter/Update feature. Both can be accessed from the Seller Admin page.