Browser extension / addon Chrome + Firefox

I need a browser extension for Chrome + Firefox + Safari + IE The browser extension will be used for facebook to add my own adverts at the side, top and bottom of the users facebook page. I have two examples of extensions which I want this one to be like. If possible can you give me a price on the extension that adds my adverts but also a price on the same extension with the ability to change facebook layout skin. Examples: [login to view URL] [login to view URL]