Foreign nationals who are not American citizens or lawful permanent residents of the US need a work visa, as well as a permit to work, officially known as an Employment Authorization Document (EAD), in order to work in the USA.Prior to coming to the USA to work, you will need to obtain a visa from the US Embassy or Consulate in your country or the country that is closest to your residence abroad. Here's a directory of US Embassies and Consulates.

Visa Requirements
If you want to work in the US temporarily you will need a specific visa based on the purpose of your travel and type of work you will be doing. In order to obtain a visa, you will need to meet specific requirements to qualify for a Temporary Work visa under immigration law. The consular officer will determine whether you qualify for the visa.

How to Find an Employer
US Exchange Visitor (J) non-immigrant visas are for individuals approved to participate in work and study based exchange visitor programs. Participants in these programs can access a list of organizations that will sponsor their visa and information on applying online. Here's more information on US Exchange Visitor visas.