Http problem - your provider might be blocking inbound requests on port 80 (default http). Some of them do this because of the Nimda virus. To get around this, you would have to change the default listening port for apache (there is a how-to on this).
If you have a provider (Roadrunner, for instance) who blocks ports, you might invest in a redirection service like easydns. This makes it easy to make redirections like
www.domain.com -> IP_Address:port.
You do have a domain registered, right?
--phil