You can't post pics directly from your hard drive. You must upload the pic to a web server that you have an account on that will host it for you, AND that server must allow linking from other webpages. The reason you see the "This photo not available" from PhotoPoint is probably because the PhotoPoint account in question isn't a PAID account, and those are the only ones that allow remote linking.
Also note that your picture will be downloaded every time someone loads this page. If you're linking from your personal web account, you may have a usage limitation (such as, only 100 MB of transfers from your web page per month, or you have to pay extra). If you were to post a 1 MB pic here, and 100 people open this page the first day, you'll have used up all of your usage credit for the month.
The days of free services on the net are pretty much over...
-Troy