Search in nav menu

Hey everyone,

I have this awesome idea to add a search icon (probably a magnifying glass or something) on the right most position of my nav menu. When the icon is clicked then a seach box will appear (preferably below the nav menu). I have a bad feeling that I will need to wirte a jQuery or Javascript file in order to accomplish this functionality, and i can research the syntax of those languages on my own. I need help with how to add the file to every page on my site and how to get the icon in my menu. My menu is currently in the header right widget, in case that matters. Any ideas or solutions are most appreciated.

Here is a link to my site: http://www.compmort.biz

here is a link of a theme that has the functionality built in already: http://demo.siteorigin.com/vantage/

Thanks for any help given