Welcome to cycling hayleyy. As Beroepsrenner said, there have been a few lists floating around, but no problem bringing the Aussies to the front again! This was my list after some obvious missed riders were pointed out by other Aussie posters. We also had to separate the roadies from the trackies. These lists are always controversial, but we have had some good riders both past and present!
Sir Hubert Opperman
Phil Anderson
Robbie McEwen
Stuey O'Grady
Cadel Evans
Brad McGee
Russell Mockridge
Michael Rogers
Alan Peiper
Neil Stephens
Alternates: Baden Cooke and Simon Gerrans
Leaving out Cookie was difficult as an ex-green jersey winner, but he never really capitalized on that form and hence I've given Brad McGee the nod instead. Simon Gerrans is also difficult to leave out as a stage winner in both the TdF and Giro and winner of the TDU, but I think some of the trail blazers and hard men of yesteryear deserve their dues. I have purposely not included Haussler, just because it is a convenient excuse that he is German this year. I would have otherwise included him, but I would know who to take out! Others current professionals that didn't make it, but deserve honourable mentions include Matt White, Matt Lloyd, William Walker, Nick Gates, Matthew Hayman, Allan Davis, Ben Day, Brett Lancaster, and Mark Renshaw, just to name a few.