Hi Cassie, I'm from San Francisco and have been living in Australia for almost 2 years. I think Sydney is a must-see. Full of history and iconic landmarks! Melbourne is a cool place, had a vibe like Seattle- cafes and art. And you've got to experience the beach / surfing culture: Queensland's "gold coast" is like Miami, with beachfront high rises; the "sunshine coast" just north of there is mellow. If you enjoy swimming at all, it's worth looking into a dive/snorkel trip out to the Great Barrier Reef; the Whitsunday islands are a great place to do this. If you make it to western Australia, Rottnest Island (a short ferry ride from Perth) is stunning. Rent a bike there to circumnavigate in a day; it's full of turquoise water, white beaches, and tiny (tame!) marsupials called Quokkas. IMHO, Uluru (aka Ayers Rock) is a long, expensive trip and probably not worth the time if you only have a couple of weeks. Good luck with your planning!

Cassie - I was in Australia a few years back, and by far the coolest thing I did was a one-day walkabout in the Blue Mountains near Sydney with the organization linked below. For the record I am in no way affiliated with these guys, but the person who runs it is incredible - his name is Evan Maru; he is half aborigine, and when I met him he was doing his graduate work studying his own tribe, which I think has pretty much disappeared in the last 50 years. So he knows sites near Sydney no one else knows about, and provides an amazingly immersive experience, even if you just go for a day.

Hope this helps! --Paul

http://www.bluemountainswalkabout.com/frames.htm

Queensland is awesome... you can drive up the coast from sydney if you like... visit all the little bays along the way and then the gold coast, then carry on to brisbane and noosa... fantastic trip!