Does Magento 126.96.36.199 CE already include the Google eCommerce tracking code?
If not, how would one implement the Google eCommerce tracking code specifically for Magento?
Yes it does. There is a Google Analytics module. To activate, insert your GA UA-code into the
System > Configuration > Google API administration area:
By default this is the GA Async version - not the new universal analytics code. After enabling and input of your UA you should then see it show up in your page source.
Events like ecommerce conversion are already built in, and funnels for checkout will populate. It's a fairly fully-featured GA ecommerce build out-of-the-box.