Glad everyone could help you so far
Just make sure you don't just go to the petstore and buy everything they say you need. Don't go overboard on all the different water bottles either. As already mentioned, good starter kit is to get some Cycle (which jump starts your good bacteria), a water conditioner like AquaPlus, an Ammonia/Nitrite/Nitrate kit and a pH and water hardness kit (often these are combined in quick test strips). Also a gravel vac.
Sometimes, there are cheaper alternatives...for example light tubes and substrate can be purchased from a stores like mitre 10 and Gardens to save lots of money! Use this money instead to invest in a good brand of heater..like a Jager, and a good external canister filter that has room for more then just a sponge (eg. at least a Fluvial 205 would be good for that sized tank I think)...it will make you life easier and less costly in the future Often you can find these at a discount on TradeMe.
When choosing fish make sure you can meet their size and water requirements and that they are compatible with each other. Best to start of with some of the hardier species and to introduce the stock slowly to give the bacteria a chance to build up. Fishless cycling is complicated and I think its best to just let the tank sit for a week and then get up to 6 hardy fish to kick start the process. In a months time you can add some more. Cycling isn't all that hard or involved if you just let it happen naturally
Give them a nice environment with shelter using rocks or driftwood. Plants are very good too but make sure your fish don't eat them or that they don't require really bright light.
Don't get overwhelmed by all the knowledge out there and just keep it simple until you get a hang of it There are heaps of Qs and As on this forum so just use the search function or browse the articles!
It's exciting isn't it! Goodluck!