I am going to marry to my boyfriend who is a green card holder. Can I apply for green card after we get married?

Yes.

Is it risky that a green card holder through marriage can sponsor her/his new spouse ? Could she lose her Green Card ?

Expect to be questioned on your current marriage, her previous marriage and your stay in the U.S.

Moving petition filed to other State

You will file AR-11 and notify the USCIS the change of address towards the application.

Can a person get an H4 visa but not stay in US?

H-4 can be used for temporary stay with H-1B spouse

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I'm in US doing tourism as B2 visa, I need to leave US to activate my H1B visa, since I've permission to start in Oct 1st?

Talk to your company's counsel and seek his advise.

Notice period to quit my current L1B employer with benefits

Have an employment/ labor lawyer review your employment agreement and determine a clean termination for you.

I330 intial reiview but i485 interview has been scheduled is this a problem?

It does not hurt to get professional opinion.

My H1 B visa is valid till JAN-2014,i have applied for extension but it is not yet approved. can my wife apply for H4 visa.

1) Yes. Though no one can guarantee entry 2) Yes, though she will get time in h-4 until Jan 2014 only and you will apply for her extension.

While Perm Labor is pending Can I switch to H4 and renew my H1B after labor is approved ?

Ideally your company's lawyer will discuss the strategy with you. You cannot make these decisions independently as the employer may decide to...

How long F-2 visa holder can stay in USA after F-1 leaving ?

The longer the stay, the more difficult it will be to get another non immigrant visa at the Consulate abroad.