I came in aug 2010 on L1 visa. Even I am married but my wife and baby are in india. My question is from which site I can file my tax and which status I will use to file tax? Will I get benefit for my family? Please suggest me. Thanks in advance.

When did you leave US?

I'll be in US for this year(2011) as well.

You have two choices.
Choice 1: You did not complete SPT in 2010, you can file non-resident tax return. You can also deduct moving expenses, use Form 3903.

Choice 2: You can file resident tax return as Married Filing Jointly. You must wait to file your tax return till you meet the Substantial Presence Test in 2011. Read Your U.S. Tax Return: Substantial Presence Test (http://taxipay.blogspot.com/2008/04/substantial-presence-test.html)
You will get standard deduction of $11,400 and exemptions ($3,650 each) for both of you. You must both declare your worldwide income for 2010. If you have any foreign income, and on that income you paid taxes in the foreign country, then you can claim foreign tax credit (Form 1116) or you can use Foreign Earned Income Exclusion (Form 2555). 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)
You will complete forms W7 (application for ITIN) for your spouse and attach with your tax return. You can also deduct moving expenses. Use form 3903.
If you decide to file as Married Filing Jointly as First Year Choice, you must attach a statement signed by both of you to your return stating that you qualify to file as residents as First Year Choice and that you CHOOSE to file this way.

File state tax return only after you get ITIN. Make sure to pay any tax due on or before April 18, 2011. If needed, file for extension.

Thanks for valuable response.
My my wife & baby will come in 10-march-11. So
Choice 1: if I file NR than what status I'll choose. Single or joint as my family was not with me in 2010. And can I do e-file like Turbo Tax or some other site?

Choice 2: As you suggest that I can file tax married filling jointly, so my question is my wife & baby will come in 10-march-11. So how can I show their presence with me in last year(2010) to get their benefits. Will it be legal. Or for this I will use e-file

1. Turbo tax will not do nonresident tax return.
2. It is joint return. You can not claim the baby as the baby was never in the US.