Tutorials apply to courses generally, and are applied according to the time available, the material covered, the number of students, etc., and for this reason tutorials will be arranged during the course itself. In general, tutorials are useful for making available help towards issues and projects specific to students - projects based on a student's own idea and therefore maybe requiring specialised information.
In most cases, while attendance at tutorials is encouraged, it is only of real value when you have prepared sufficiently. There is little point in announcing that you haven't actually done anything without having anything further to ask, although even then progress can be made in helping you decide what you might want to do or how you might approach a given task. Tutorials can, if used properly, be one of the most valuable resources you have, so please take advantage of them!