For all domains on my account if I enter the full url into browser the site won't load. If I search google for the sites and click the link from google, they open instantly.
Are you using the opera browser by any chance? if so it routes its requests via a specific IP which may be the reason why when you check google search results your site pops up as that IP may not be blocked. FYI if you have CFS (config server firewall) installed make sure your not blocked there in any of the ban lists as info prostated.