Alley,
First of all, welcome to the US. One thing that will come to your attention very quickly is that at this time of year LV is very hot and the sun's rays can be unforgiving so dress appropriately. I noticed you are an Aussie so perhaps you can relate to the weather, especially if you have visited the desserts of the Australian Outback. To put it in your terms, temps of 40 to 45 deg C (104 to 113 deg F) here in LV are not uncommon. As Baz Luhrmann once said, “Make sure you have plenty of sunscreen.” Next, for the info on what to do, here is a useful site I use from the local chamber of commerce:
http://www.lvcva.com/ will give you a good overview and for specifics on what other travelers like and to help formulate one’s plans I sometimes go to tripadvisor.com for LV it is
http://www.tripadvisor.com/Tourism-g45963-Las_Vegas_Nevada-Vacations.html. Also, to get an idea of what locals and tourists think of particular dining, bars, clubs and other establishments I would also check on Yelp.com,
http://www.yelp.com/las-vegas. And the last thing is, have fun and enjoy the trip. There is quote from a local broadcast news person, George Knapp that I think says it all, “Greetings from the boldest, bawdiest most outrageous city in the world, the planetary capital of sun, fun, sin, sex and secrets, my not so humble hometown, Las Vegas, Nevada.”