as an international student you are not eligible for discounted public transport tickets. such tickets are concession tickets and you need a valid concession card to prove you are eligible. actually anyone can buy the tickets but you risk being asked to show your card to prove youre eligible to ride on such a ticket. ive been in Sydney 11 months and pretty much have never been asked, however, i have a valid card.
food: cheapest food is rice and beans. brown rice is 29 cents/kilo and dried lentils are a little more. cook them up in mass quantities and freeze it. i mix the two, add a little home made salsa, a little frozen mixed veggies, and a little low fat cheese. dirt cheap, really healthy, and quite tasty. oats for breakfast is cheap and healthy too. just dont buy the individual packets or the quick cooking stuff. the individual packets are just a huge rip off and they all actually cook in about the same time, but the regular tastes better than the so called quick cooking.
as others said, live farther away but near a train station. but what train station is important. having to switch lines even once can significantly increase you commute. try to stay near a line that goes directly to your destination.
home appliances: i just shopped around, but i bought new. 2nds world usually has great prices. do not be afraid to haggle here. unlike the US, you can negotiate most prices here. as for used, check out gumtree.com.au. its like craigslist.
clothing. it expensive here. try to bring it with you. i just had levi's shipped from the US cuz they are 130AUD here (115USD with current exchange rate). you can always do the 2nd hand stores, but ive yet to buy anything more than a dress shirt here and didnt like having to pay 50AUD for it. it was the cheapest i could find and the sleeve length wasnt even measured; it was 'regular'. thus it will be cheaper and you will have a a much better selection in the US (guessing canada too).
if you drink beer be prepared: beer is outrageously expensive here. i could buy a 6'er of coopers (made in Adelaide, S. Australia) back in boston cheaper than i could here. they tax the hell out of alcohol here. best solution is to homebrew, which i just started. it easy and cheap as hell. ~20AUD for 2.5 cases.