I see lots of refernces to using the update manager, but where on earth do I find this??
Cannot see anything at all relating to it on my version of Ubuntu 12.04
Unity Dash. This is the easiest way to see the Update Manager:
If you tap your Windows Key (Super Key) it will open Unity Dash. Another way to open the Dash is to click the Ubuntu Logo on the Launcher (The Sidebar to the left). If you just type in 'Update Manager' you shall see the icon in the search results. The reason of you not seeing the updates is because the updates are not really important. A warning: The updates may be 300 or more because of you not using it for ages.
Hope this helps!