Hello, I'm owner a company in VietNam and TX, US. i would like to apply Visa L1, what i need to do? please advice, thanks.

An L1 is appropriate if you can demonstrate that you need to be in the US for a legitimate business purpose, that you have sufficient funds, that...

Do I need a joint sponsor?

Simply attach a letter from your employer verifying your position and annual income.

Will American face harboring crime if living with illegal immigrant boyfriend/fiance? What if married?

You guys should go an meet with an attorney. With a waiver, if necessary, the "illegal" immigrant can gain permanent residency.

Adjust of Status with approved i130 - Petition from US Citizen To Wife

If your wife was paroled into the US, she can adjust. Whatever annotations are on her passport, she should show them to her attorney.

How to handle h1b visa transfer?

There is no "transfer" per se. You can start working for a new company as soon as it files H1B petition for you. However, you need to consult with...

You cannot. The reason is that EAD is based on your pending application; however, there might be some options. You need to consult with an attorney.

How long does it take to get an L1A to L2 conversion done without EAD?

You can check processing times at www.uscis.gov. It should not take too long, but each case is different.

What would be some reasons my citizenship application wouldn't get approved?

There could be many reasons starting from failure to pass English and history tests , and failure to meet basic eligibility. You need to meet with...

Can I travel to Mexico I-130&I-485 is being processed on H1B valid till Dec 2015. I applied for I-131 but don't have it yet.

Yes, you can as long as you have a valid H1B status/visa.

I am looking for an International Immigration Lawyer who handles Spanish Citizenship, Do i have to sign my U.S. Citizenship away

Attorneys here can advise only on the questions of US Immigration law. I would say that if any state requires you to give up your US citizenship,...