如何防止深度链接到我的网站上的文件

I own a website which contain a lot of freeware stuff to download on it. The problem I'm facing is that people from around the world are taking the direct links of the files (for example .zip files) and posting them on their websites and general forums. I am getting a huge amount of bandwidth and that's ok, but the number of pages visited is low. Is there a way or a script that I can add to the links, so that when someone presses on the link from a foreign website, a page from my website opens instead, which then lets him download the file so I can get more visits.I own a website which contain a lot of freeware