Website Licensing script/code

I want someone to write a simple secured PHP/MYSQL script that i can put in my finished website code so that whenever users browse the website, the script looks up my database table away from that website and decide on an action if the website is not registered there on the table. This means that at first launched of the installation with any domain, it prompts the owner with a registration form to register the domain on which it is installed. The form information is recorded to my database table on my server. The website won't work on Any domain not registered on my server database table. It should display a message on browser telling the user to contact me through an email i will provide there on the page. if you have a better idea of implementing it, let me know. If you can or already have one to sell, lets talk.