Employment in Central America can be found as a volunteer or in a tourism-based job. Several English speaking communities have sprung up and especially cater to job seekers from the U.S., Canada, and England; these are Ambergris Caye in Belize and Roatan in Honduras. Panama is also a country that has a growing English speaking population and can be a source of job opportunities as well. If you are a U.S. citizen, I’d recommend staying out of El Salvador and Nicaragua due to safety concerns. Spanish language skills are not required but do help with finding a job. Guatemala has successfully marketed itself as an inexpensive place to study Spanish and has a lot of schools that offer intensive classes.
Employment in South America can be found as a volunteer or in a tourism-based job as well. Spanish language skills are also not required but do help with finding a job. When I traveled through Peru, Argentina, and Colombia, I was surprised to see that there were a lot of job advertisements for English teachers but they only paid $7 to $9 per hour! The higher paying teaching jobs are found in the Universities but, generally, you have to have a Masters degree to obtain one of these jobs.
There are also jobs to be found as a translator (both speaking and writing), tour guides, hotel staff, Internships, and volunteer positions. For some reason, unknown to me, Brazil is the most difficult country to obtain a work visa and find employment as a foreigner.