Well let me tell you something, you have nothing you could do. First of all complain about the teacher you cause conflicts. Second of all this is what happens to most Computing subjects, you're generally up on your own for it. I remember i got flammed on this forum sometime last year, for saying that i wasn't told certain aspects of topics were tested, and they just threw it in, without notifying us, and people just kept saying that it was up to me to do the studying, but then i'm like i would not mind to study myself, that's if i knew what NEW topics were gonna be put in, and furthermore i had no text book. So all i can say is the Official BOS needs a total review of Teachers, actually more like a damn audit on their knowledge, for the ones who teach computing, because quite frankly they know nothing, and that dissapoints me, no matter how much BOS changes the syllabus to be better, when you have a poor teacher giving you no feedback, and misleading you with their knowledge, they're really gonna screw up your HSC, i was lucky to have a good share of computer teachers at school which i can approach. But most of the time it was some common knowledge since i liked Computers. Simply most students nag and hate SDD, but i like it cause i had a teacher that taught, as opposed to some who just had teachers that knew nothing, and the student knew more than them.
As for studying, i'd strongly advise you to grab any, even all the IT Exam papers, go through them all and mark out the ones you're not getting, and i will be able to help you, so drop a post in the IT forum.