Hello, it's been a year now (I think it's two) since I've visited and asked a question.
Here's the deal:
1. I was on a L1 Visa from January-November 2011. But was outside the US from January to April.
2. Based on my L1, my salary is paid by the subsidiary company outside the US, at the foreign company. Tax returns have always been filed there.
3. Late November I got my GC
4. December I got a contractual work for about $9000.

How do I file my taxes now that the situation is more complex than it was? Am I entitled to tax refunds/credits?

Thank you so much!

It appears that you completed SPT in 2011 so any income earned during that period is taxable in US even when it was paid outside US. You will file Dual status tax return or resident tax return depending upon when you entered US. If you file dual status income the income earned during resident period is taxable. If you are resident for full year, report worldwide income for the year. Your U.S. Tax Return: U.S. Citizen or Resident with Foreign Income (http://taxipay.blogspot.com/2008/03/us-citizen-or-resident-with-foreign.html)

When the OP got his Green Card (GC), ALL world-wide income became subject to U.S. taxes, even if earned OUTSIDE of the U.S.

Now, if the green card was NOT a factor, then income earned OUTSIDE of the U.S. by a visa holder BEFORE he meets Substantial Presence is NOT subject to U.S. income taxes.

You will have to file Schedule C and SE for the contract work.

If you want my professional help, double-click on my title above and then scroll down to my profile/signature, where you will find my email address.