For the search button and input field, taking a few steps back, what you are trying to do is use JavaScript to access a value stored on an HTML element. That is where the DOM APIs come in really handy. All you really need is a way to identify the HTML element, and then you need a way to read some property on the element that represents the text to display. All of this needs to happen when a button gets clicked.
The code here covers all of that, though for a different example: PHP field validation Let me know if that helps 
Cheers,
Kirupa
