EDIT: Ahh, this work was bumped earlier - was not aware. For anyone using music and images in this subcategory; websites, multimedia etc:
Yes, credit work, Copyright Act 1968 says you can use acknowledged work for the purposes of 'research, education, criticsm or review' or something like that.
Credit everything, if possible - what they love if you send an email to the author asking permission - and put it in your Journal. That way, you are certain that you are free & clear, and if your Journal is reviewed (and the number of journals they are reviewing is growing!) it will shed a great light on your work.
While you aren't doing this commercially, its always best to credit and wherever possible let the author know. Though you don't have to, of course. I do hear that the markers - (source: 2 of our English department that share the Ext.2 class this year are HSC markers) are cracking down on copyright like never before. Be careful, and good luck.