In that tutorial, Tom used subfolders in his project to organize added objects. If your touch object is not in the "input" folder, it won't show up when you go to add actions and go into the "input" folder. To move it in there, you can just drag it into the folder in your project bar on the right.
Otherwise, it should work fine even if it isn't in the input folder. Just add event - and look for the touch object in the initial list.
If you haven't added the touch object at all yet, you can do so by right clicking "Object Types" (or the "input" subfolder under it) in the project bar, and click the "+ Add new object type" option.
Edit: Note that using subfolders for objects is not always necessary - I've never bothered with it myself.