Most ISPs, e.g., Comcast give each user some space to post files on the Internet. I have uploded files on Comcast, so I know that works. Who do you use for Internet connectivity?
Another option is a site like
http://www.sendspace.com/. I have never used it, but hear you can upload files for free.
In either case once a file is uploaded, you will now have a link which you can share.