A 404 error may mean that you successfuly reached the server where Amiga.org is but the web page you asked for wasn't there. Did you double check if the URL, with nothing after the ".org", works?
Also, kolla's advice is very good. Make sure the server you reached is Amiga.org. A while back my ISP fell victim to a DNS poisioning attack, and oddly enough, one of the sites that was misdirected was Amiga.org.
