Compared to maths and sciences, there aren't a lot of practice exams, but certainly there's more than enough.
First place to start is VCAA. Have you done last years exam yet? What about the sample questions?
Don't just do the exams, actually sit down and analyse evaluate where you can improve, where you struggle, whether your answers are as clear and straight to the point as they could be etc. afterwards. Then there's Mark Kelly's solutions and the VCAA assessor reports to go through.
That'd be the current study design done with. Then there's all the previous VCAA exams to do. It's easy enough to pick out which questions are relevant and not, you'll have a a fairly good understanding of what the current study design consists of by now. I was only really going to leave it at VCAA 2007 onwards and multiple choice from 2002 onwards, but going by Paul's suggestion I'll just go for it and just do all of 2002 onwards.
Along the way you should be picking up your weaknesses and exploring those areas in depth - simply rereading notes probably isn't enough, you might want to jump and google and find out more etc.
After that, current study design practice exams produced by the companies. Same thing with these, research what you're unfamiliar with, learn how to tackle particular types of questions. You could do the old study design ones of these if you're keen, but I'm not going to bother - they don't stick closely enough to VCAA as it is, so it'd be worse with older ones.
Personally, I'm doing a bit of prioritising, so I'll be going a bit light on the SD revision over the next week (probably just do one exam, go over some of the content and some of the worksheets for various topics) before really going all out on it. That's just the way my exam timetable has worked out though.