Welcome to the enquiries forum. this is the place to ask questions relating to our books, our courses or the school. If you have a more specific problem relating to aviation theory, check out the Question and Answer forums. That's the best place to post your technical questions.
A few things have changed over the years and perhaps the best way to get back up to speed would be with a good instructor, CASA has an online store now where you can purchase the Visual Flight Rules Guide which outlines much of the sort of thing you will have be familiar with.
You can also get a few other items for free but there is a $15 postage. Bob Tait has a great reference guide to air law that I find very handy as is his Air Law book, might be worth making a purchase on these also.
From memory what was once an MBZ is now a CTAF and GAAP zones are all class D, procedurally I can't say what has changed with these as it was many years ago. Airservices has some videos etc on how to file in NAIPS etc, this process has changed a bit over the years and most of it done on the net these days.Have a look at their website too that might help you get up to speed before you fly again.