Queries regarding divorce

- I have an offer to move to USA for long term. Will it good that i left India without informing her. And all the legal action will be taken care by my Advocate.

In India, leaving your entire litigation to the mercy of your advocate is like giving a blank check to your wife (and to your advocate). Any person who starts litigation in India and leaves it all to his advocate must be either mentally retarded, bed-ridden, eunuch or totally illiterate. Do you fall in any of these categories? 

- As she allready have Visa. Will she able to create problem in USA if she comes? Its an expensive country she won't come.

If she has visa and she comes, she will be able to assert her legal rights as your lawfully wedded wife in U.S. Courts. U.S. advocates would seize the opportunity to sue you... She can work out a contingency fee agreement where she has to pay nothing to the advocate but the advocate will get a percentage of whatever you get. Such arrangements are perfectly legal in US. 

- I will be lawable to Indian court or USA Court?

You are liable to ALL courts in accordance with the laws in that jurisdiction. In U.S. your wife will be protected under the local laws of the specific state in the U.S. as matrimonial laws are state specific in USA.  She can also, and simultaneously file cases against you in Indian courts irrespective of where you are geographically. I am presuming that you are both Indian citizens. 

- After going there can my advocate file a diavorce case on my behalf. I mean to say any legal process i want to start once i reached there.

Refer to the answer above... 

- Which is good to handle the case from India or USA?

If she files, you don't have a choice. If you file in USA and she is in India, the decree will NOT be valid in India unless you can prove that she had and was given full opportunity to litigate the case and further that she could do so.

- Maintainece oe Allumeny will be based on Indian salary/style of leaving or USA Salary.?

Depends of where it is filed... India, USA, Europe... there are different standards and laws for maintenance... but in general, its not a pleasant scene to look forward to.