The main administrative office that will be there for you is the Graduate Student Office. They are the ones dealing with your registration and they tell you what your fees are etc. You might want to look at the different forms that are useful to you.
The second administrative office you need to pay attention to is the one from your own program. If you’re a Teaching Assistant, you need to make sure to talk to them and the instructor if you have questions. Your office space will be assigned to you by your program.
Some of you will be Teaching Assistants (TAs) at Trent. The Trent Instructional Development Center is providing TA training during orientation week. There will be a few workshops to which you might want to register. The person to contact about this is Angie Best.
In addition to these workshops, I would encourage anyone who feels uncomfortable with public speaking or simply giving intro talks during labs to ask their fellow TAs for some help and support during the first few labs so that you get used to the classroom environment.