How to test if a google analytics code works?

In Chrome:

• Right Click anywhere on page
• Inspect Element
• Click Network Tab
• Reload Page

Look for:

• Type 'image/gif'
• Method: 'GET'
• Name (starts with): _utm.gif?

Look for the __utm.gif tracking pixel request. A few different ways of doing this are:

• A web debugging proxy like Fiddler (my preference)
• The Network tab in Firebug or Chrome Developer Tools.
• The Google Analytics debugging script ga_debug.js will log tracking requests & errors.
• Google Analytics Tracking Code Debugger is a Chrome extension that enables ga_debug.js.

The analytics code on the page probably has a _trackPageview, so as the page loads you'll see an initial __utm.gif.

When _trackEvent fires, there should be a new __utm.gif request being made. Parameters to examine in __utm.gif URL are:

• utme=5(Outbound Linkslabellink.href) -- _trackEvent parameters
• utmac=UA-1234567-8 -- the analytics UID

Also, (as pointed out by @Eduardo), take a look at Google Analytics Basic Debugging