Elyse, I wouldnt be in rush to get new eyepieces untill you get to know your way around the sky. The ones that came with the scope will be fine for now.
As Stu has said try and get to Astronomical Society, the members will be more than happy to help you. That way you can try different eyepieces before you buy to make sure you know what to expect.
Astronomical societies in melbourne/Victoria.
Astronomical Society of Victoria
Mornington Peninsula Astronomical Society
Snake Valley Astronomical Society