What are some things to see/do that I can't just "wing it" when traveling around Australia?

I have just the thing for you! There is a website where you can find more interesting experience provided by real local Aussies, and the best part is that it's very flexible. There are some really unique things like; a graffiti walk with the artist in Sydney, chocolate experience in Adelaide, best of Brisbane walk, small bar discovery in Sydney CBD, North Stradbroke Island experience in Queensland...and many others, but they are all genuine and cool things to do. I recommend checking it out: http://arribaa.com/ Hope that helps mate!

If you want to meet locals, be sure to check out the small towns throughout.  Pick up a small town paper and look for events like Saturday markets, dog sledding (dirt), sheep shearing, surf contests, watch a kids footie game.

In Australia in July there is really nothing that you will find booked so solid you won't be able to see it within a day or so. The exception would be some of the theatre but even then you would be able to find something good to see, just not perhaps one or two particular productions. If you want to see a performance in either of the two main halls at the Sydney Opera House then I'd pre-book those. Understand, however, that you a actually see more of it if you do a tour than if you see a performance there.

I can advise you about the Sydney area as I am moving to sydney in 2 weeks and checked out what to do in winter. Visit Blue Mountains and  Botanical Garden, have a stroll on the beaches, walk the inner-city, visit sydney aquarium. Here is a website that can be handy: http://www.sydneyeguide.com/attraction.php

#1 must see while you're there is the reef http://www.gbrhelicopters.com.au/tourism/reef-packages/ I'm a laaady and laaadies drink wine and I would love to go to a winery! Much cheaper than Napa! http://www.yarravalleylodge.com/visitors-guide-yarra-valley/wineries/ Sovereign Hill is something my parents would love, but not sure what you're into. http://www.ballaratlodge.com/ballarat/attractions/sovereign-hill-gold-fields

It kind of depends on how much time you have. We had a few days in Sydney before four weeks for Brisbane to Cairns. (I wouldn't have wanted to go any faster than this, we still had things we missed out on at that pace. My friends were on holiday for six weeks and I was there for a year.) The first day was taken up with being extrodinarly jet lagged, the second day we went to a local travel agent and pre-booked Fraser Island and the Whitsunday Cruise. Both of these tend to get booked out a bit in advance. Of these I would say the one I would recommend booking in advance is the Whitsunday Cruise, for a few reasons. Mainly because it's worth researching a decent boat, don't go for the cheapest option they tend to be loutish party boats. Some of the idiots on our boat didn't snorkel or dive once! We would come up raving about turtles and clown fish and coral, they would be starting on the hair of dog. The other reason is that while a night or two in Airlie beach is a bit of fun, a week would be way too much time there. Diving and snorkelling off the Whitsundays is pure finding Nemo, it was much much much better than snorkelling from Cairns. If you have a couple of days to spare to get a space on a Fraser Island camping trip, then I wouldn't worry about booking in advance. There are lots of beautiful places to explore in the area. I could have spent more time there, as it was we didn't have time to do a whale watching tour. Red Center. I would really urge you to try and see some of the Northern Territory while you are there. It's the perfect time to visit, no flies, dry, heat is managable.  But I would recommend that you go to Darwin and explore Kakadu or Litchfield NP rather than the Red Center. Kings Canyon, the Olga's and Uluru are stunning, really beautiful, but it's expensive and feels like a package holiday. Look at doing a swag bag tour, dawn in the desert in a swag bag is just the most amazing experience.

It really depends on what you want to see, how much time you have and how much money your willing to spend. If you are here for only a short time (1-2 weeks) you may want to focus on the major cities where you can just 'wing it' and book flights to another city as and when you please.