First, you'll need to define the _gaq variable and load in the analytics script from googles server. After that, you should be able to call the 'push' method.

var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-XXXXXXX-X']);

(function() {
  var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
  ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '';
  var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);

// tracks hit for /some/page/
_gaq.push(['_trackPageview', '/some/page']);

Be sure to substitute 'UA-XXXXXXX-X' with your account ID.

After that's done, load up the page in your browser, open up the console, and look in the network tab. Try loading a few pages to verify that it's asynchronously pushing data to googles servers.

Google uses a .gif image for tracking, so you might try filtering by image and to find request for a file called __utm.gif

Google Analytics Tracking GIF

If you're using Google Chrome and still having trouble finding it, you might try the tag debugger plugin by ObservePoint or the Official Tag assistant plugin by Google