Yeah, overseas hosting is the way to go. I think you can probably use a FTP over VPN to do the uploading to the site if you want to be really anonymous. As for paying for it, perhaps a pre-paid cash card purchased with cash? I've always thought that might be a great money laundering system
If you had a site over here but connected to it via VPN then you're still governed by UK law. Especially as the VPN would need an endpoint. Overseas hosting would be the best bet. Still intrigued though as my hosting company allow legal adult content so what on earth are you hosting?