Facebook Like Script Source

Hi Freelancers!!! We need a facebook "like" script that stops viewers from seeing the facebook page unless they LIKE the page. We have seen this script being used on quite a few pages, now we just need the source code. We will pay 30$ if you can provide the source code AND show (demonstrate) the script actually working. I believe script uses a php/javascript lightbox to block the page and i also believe it uses FB markup to link into FB. Thanks! Shaun Twin Helix Design Studios