US Tax help

Mark VTD hasn't posted on the site in a while, he would be one of the better resources for the information your looking for.

Being cheap (tight) I use free tax programs to file my returns in the three countries I file in.

Check out: [ http://www.reviews.com/online-tax-software/free/ ]

Using accountants here in VN for overseas filing is expensive (in VN the accountants are much cheaper). The corporate tax preparer we use in VN is a former Tax Department employee.

One of my colleagues told me he simply declares the income - without supporting documentation - and it is accepted. His tax guy said hookers also simply declare the income!

I also file using an address based on the country I file in so I look like an in-country filer.

The US needs every dollar it can extract from personal filers, given that big corporations like Apple, Dell, Facebook, Google, etc. are 'moving', for tax purposes, out of the USA. The last notable one was a hamburger chain that is merging with Tim Horton coffee and 'moving' to Canada.

The USA and VN have a tax agreement, so offsetting is easier.

Jaitch, Apple, Dell, Facebook, and Google are not "moving" their headquarters out of the US for tax purposes.  If they were to do that, the public backlash against them would be so severe, it would cripple their businesses.  Apple's corporate headquarters (as well as engineering, etc.) are in Cupertino, California and they file taxes as a US corporation.  Apple as a corporation is the highest single taxpayer in the United States.

You are possibly conflating the issue of foreign earned revenue, which Apple has a significant amount, in the neighborhood of US$40 billion that they have not "repatriated" to the US because of the 35% tax it would incur.  The word "repatriate" is pretty ridiculous, because the money was never in the US to begin with. 

However, you are correct about the hamburger chain (Burger King) and Tim Horton's corporate inversion/merger that was recently announced.  Considering the relatively small size of those two companies, and the amount of furor it generated, if Apple, Dell, Facebook, Google, etc. tried to do something similar, it's safe to say the public outcry, and never-ending negative publicity would make the move suicidal for their businesses.