Yes, Lemarre, it's all to do with the size of the trade.
So if you buy 1 lot, the tick size is $0.07 (or equiv. in your currency). If 2 lots then the tick size is then $0.14 and so on.
As for brokers, you'll find loads offering the US30 (they can't call it Dow because of legal reasons). FXCM, Oanda, maybe even your Aussie brokers like IC markets etc. All will accept small accounts.
And as others have said start to paper trade to get a hang of things, including the software used etc. Iron out all the stupid mistakes you'll be making at the beginning like clicking buy when you meant sell etc, we all do it