each browser has find on page functionality (ctrl+F). Is there a way to detect user searches in javascript so that I could attach additional actions.
You could do (to detect whenb a user press ctrl+f):
window.onkeydown = function(e){ if(e.keyCode == 70 && e.ctrlKey){ //user pressed ctrl+f }
Fiddle here: http://jsfiddle.net/d8T72/