Making your own soil is probably the best thing to do- if you get a good recipe and I guess also know the idea behind it. You can get perlite, peat moss and coco coir from bunnings but you'll have to find earth worm castings or compost locally from a proper source. Using 'compost' from a brand name bag isn't the same thing and is likely too hot with the added manure and what ever else they put in it so it can be used as a top dress fertilizer).
To be honest though for this grow i've just started i'm using Canna terra proffessional. It's a mix of some high quality german peat, perlite, coco coir and earth worm castings. It's expensive but it's good quality and if you are doing organic you can reuse the soil rather than chucking it out and buying from scratch for the next grow.
As for other things i'm using Seasol for a start as a cheap kelp soil conditioner. Buying a 2L cask for $16.97 at Bunnings and using it at a dilution of about 25ml per 9L once a week lasts ages.
I haven't used it yet but I just found a product called GoGo juice. It's made using compost, manure and kelp but what it is is a microbe brew. It seems to be a store bought version of a actively aerated compost tea which is designed to bring the soil alive with beneficial bacteria rather than deliver NPK directly. I would seriously recommend either doing AACT and other microbe brewing recipe's you can find on here or if that's too hands on buying this product. It's about 16 bucks for 1L and you use 15ml for 5L water, which apparently will cover '1 to 2 square meters'. I'll be looking into brewing my own things more later but to begin with when there is so much to learn and switch over to i'll be using this GoGo juice as a cheaply priced short cut.
I've got aloe plants growing in the garden and am starting to use it in a foliar spray as a growth promoter.
Going to also make a sprouted seed tea using Barley to be used a foliar and soil drench.
I want to work my way towards something like a no till ROLS but to begin with I'll use an organic bottled fertilizer like charlie carp, top dressing with EWC and will start looking for things like alf-alfa to brew into food.