I actually don't see any fault in your code. It's true the example uses the jQuery prototype("fn"), however you can manipulate $.find as well. I've basically copied the same code you provided in the following example:
var oldFind = $.find;$.find = function() { console.log("something new."); console.log(oldFind.apply(this, arguments));};$.find("div");Realize, you may be executing this in a specific way. Above you have:
(function() {...})();This makes the code within the first parens, self-executing(correct me if I'm wrong here), which may not have the intent desired if you call the contained code outside this function. A working example of the snippet above is here: http://jsfiddle.net/nuPLV/