Wow I didnt even realise anyone else was in Melbourne here, I don't live near clayton so I don't know any stores in that area, but for electronics components I would try Jaycar (http://www.jaycar.com.au) or their wholesaler Electus (http://www.electusdistribution.com.au), Altronics (http://www.altronics.com.au), Radio Parts (http://www.radioparts.com.au), Adilam (http://www.adilam.com.au), ummm thats all I can think of right now, I might be able to come up with a few more when I get into work again on Thursday morning..
hope this helps!

one more link, this is very handy and has tons of links, scroll down near the bottom for more suppliers..
http://www.ee.latrobe.edu.au/~mg/ic.html

oh a couple more, if you dont mind paying a lot for parts, say you are in a rush.. RS components or Farnell are a couple of places we use sometimes..

Hope you like it here!