I am a US citizen living as a permanent resident in Australia (married to an Aussie). I need to incorporate and have been advised to get an 'off the shelf' Delaware Corp. We are considering moving back to US in the next 12 months, are there advantages/disadvantages to skipping Australian incorporation and just doing it in the States? Do I need to be living in the US to incorporate in the US? or...should I consider incorporating in Australia and creating a US subsidiary in Delaware?
First, the advantages of incorporating in Delaware are frankly overstated. You'll probably spend more money and time dealing with it than you'll save in any taxes (unless you live in Delaware). Nevada actually has better tax advantages, but I would never recommend incorporating outside of where you live.
If you want to run the business, and you're planning on moving back to the states (permanently?) I would suggest setting things up in the states. Where ever you incorporate, you'll be subject to the laws of that country, obligated to pay taxes in that country, and must maintain a business address in that country. As someone who has businesses in the UK and the US, this is not the easiest of ventures to undertake.
From the information given, I would suggest waiting until you get to the states, or start working on the process now.
If you can provide more information, I'm happy to expand this. Things such as: