I usually get mine either from the health food store on Smith Street, Fitzroy - near the Johnston Street corner. Sometimes they have to get some in, but usually it's OK or the other place I use is Storm in a Teacup, up near our shop on Smith Street, this time the Collingwood side - it is between Gertrude/Langridge Street and Victoria Parade. I have purchased some from one of the organic stalls at Vic Market, but it was from Columbia and it tasted foul - in fact, I threw it all out it was that bad.
I'm not sure about the raw cacao powder - the first place I would try for that would be Monsieur Truffe (yes, you've guessed it, on Smith Street again). His shop is near the Langridge Street / Smith Street corner, next to the Japanese restaurant called Wood Spoon (even if he doesn't have what you are looking for, his chocolate is absolutely out of this world!). The health food shop on Smith Street may also have some as I noticed last time I was in they have widened their range a bit in this area.
Good luck