If you have Google Analytics tags installed on your website and need to see if the tags have been installed fine you can check using the tool SiteScan at www.SiteScanGA.com. You can sign up to have the tool crawl your site and check for implementation errors. Examples of errors could be pages that don’t have tracking code or pages that have both ga.js and urchin.js code on them (you shouldn’t run both on a single site). This is not a Google-supported or developed tool.

The tool is free for the first 100 pages (I think .. or is it 30 ?)

From the site:

SiteScan checks the following on websites with new tracking code (ga.js):

• Every Page Tagged with New Tracking Code
• Every Page Calling the pageTracker._trackPageview(); Method
• Every Page Declaring a Google Analytics Account
• No Old Tracking Code Found
• Query Parameters Check to Determine if a filter is Required
  

Limitations

SiteScan Does Not Scan or Complete the Following: 

1. Directories with more then 1000 files
2. Pages that are protected by a Robot.txt file (meaning that if your pages are not indexed by Google, they will not be scanned).
3. Pages that are password protected
4. Checkout Pages or any area of your website that requires a certain sequence of events or trigger
5. Non-standard GA Tracking Code (requires to be inserted as issued by Google Analytics)