Can i change the User an Action is associated with? After appending an action into a blend file, is it possible to associate the appended action with a specific user? 

If I append actioned geometry or nodes, typically the action moves with them; but if I just append the action, then I will get the action datablock appended but without being linked to any object. How can I link the appended action to the required object on the stage (or somewhere else)?

Sorry it is a bit of an awkward question; I hope it is understandable. Let me know if you require any further information.

Sept
You link an action to an object not the other way around. You do this by selecting the object then choosing the action in the action editor.

While an action can be used by any number of objects, you can only have one action linked to an object at one time. To have an object use more than one action for an animation you use the NLA editor to mix the actions together.