Beware of the Qantas Club pass. People who have AMEX QF Premium cards get two guest passes each year, and these have an expiry date. However, from memory, they can only be used in Qantas Club, not partner lounges such as at LAX.
The esta Visa Waiver is only valid for 90 days, so you will have to re-apply online. https://esta.cbp.dhs.gov/esta/applic...execution=e1s1
As you are entering the first port of call within the USA you will have to clear customs/immig, but then I would suggest if you have a few hours get out of there and even possibly visit Venice Beach (It's like going to a zoo in any event), but a lot of fun and some nice places for lunch etc. Nearby, so cab fare not so expensive.