Welcome to the world of sewing
I'm not too sure where abouts your from in Melbourne, but there are afew places/suggestions.
Firstly, as your new to sewing I'd pick up a 10metre roll of calico from Lincraft for $30. This is a cheap fabric you can use to "test" your patterns, e.g make a sample out of the calico first, then out of your good fabric. I swear by this stuff. For some reason spotlight doesnt always have it, and they charge up to $12 per metre for calico, so its best to buy the roll.
Secondly, one of my favourite places to go to fabrics is:
GJs Discount Fabrics, they are in Carlton on Nicholson St. They have a customer car park behind their store, and have 3 levels, with piles of "scrap fabrics". I bought cottons and lycras for afew dollars a piece, when they are normally 10-30 bucks per metre.
Op Shops - not all the op shops have a "crafty/fabric/etc" section, but some of them do, and you can pick up metres of metres of fabrics for perhaps $5-$15 dollars. Ofcourse, give them a good inspection to make sure they have no stains/weird odours, and give them a very good wash or two, followed by an iron and its pretty cheap.
Some of my favourite fabrics have come from op shops.
Spotlight - you have mentioned this one, i'd suggest getting one of those VIP cards (they cost nothing) and when theres a sale, sometimes they will send you a $10 gift voucher, or discount on special fabrics, usually theres a regular price and a 'vip price'.
Its only happened afew times, but sometimes i get the email from a friend who gets emails from spotlight, and i get the "spend $100, and save $40", so basically i get $100 worth of stuff, for $60.
Other then that, have a look at etsy supplies/ebay de-stashes/garage sales.