Do you have your student log-in details?
Go to myhub.newcastle.edu.au
If you've never logged into this before, use your UAC number, and I think your DOB for your PIN(?) (It should specify this on the log-in page I think)
You need to enrol in your courses before you can view the class timetables. Once you've enrolled, you can view the different options for lectures, tutorials, etc.
Log onto the Online Registration System to find out when you can register for these classes, then on the specified date(s), sign in and book your classes (this is a "competitive" system of first-in first-served, so it's best to do it as soon as the registration system opens)
If you need help with stuff like enrolment, give the Callaghan enquiry centre a call on 4921 5000
Hope that helps =)