Hey Mark,
If you're just looking for advice on installing GA code on your pages, then the simple solution is to just grab your Google tracking script from the Google Analytics dashboard and place it before the closing </body> tag on any landing page templates you use in Marketo. Then approve any existing pages that use those templates and you should be set moving forward.
One note- Because your Marketo landing pages are on a subdomain of your website, rather than the top level domain (info. or pages., etc), make sure in your Google Analytics script settings that you have the "subdomains of [yourdomain]" activated. It adds a slight tweak to the script itself so that it accurately tracks regular website traffic and landing page traffic in the same place.
Hope this helps!