A visa to work in the USA must be obtained through the Immigration and Naturalization Service (INS), a division of the USA Department of Justice. USA embassies or consulates abroad do not have the authority to grant work permits for a visa. In all cases, permission to work must be obtained in the USA by an employer who wishes to hire you. This can be a long and extensive procedure, requiring the employer to prove that there are no qualified USA workers available to do the work.

After your employment sponsor has been granted approval for you by the INS, it is up to you to apply for a nonimmigrant visa by completing a Nonimmigrant Visa Application. Be careful to answer honestly, as the INS maintains meticulous records and can easily check whether you have previously had a visa refused or canceled.

This is just a sample of what you'll find in the complete USA guide.