Hi I want to transfer my visa to different employer.What is time period of & transfeering & how soon I will be start working with my new employer.& wh

Not all employment visas can be transferred to another employer. What type of visa do you hold? Assuming your visa can be transferred, the new employer can file a petition transferring your status to their company. You may begin work upon receipt of the case. It is advisable to wait to start work until the filing receipt is received. You can read more about work visas at http://myattorneyusa.com/work-visas.