Whats the Right URL!

I made a flash soundboard .swf that I would like to host in post.

The issue is hosting the file from my wp installation.

putting the file in the content folder uploads then trying to link to it.
But its just always a page not found error. I put the file in google docs and linked the the preview and it worked but only for that preview url which is only one time.

so how the heck can I host a file that is public from wordpress so that I can link to the url?

siteurl.com/public_html/wp-content/uploads/file.swf does not work.

I tried creating a new folder and setting the permissions to 755 still no go yet.

Thank you in advance