How does it work when a US citizen wants to work in another country?

Every country has its own rules, but I'll give you a more general answer so that you get the right mindset.

Basically, a country's government has to take care of its citizens first. As you probably know, we have a worldwide recession. About 25 million Americans are either out of work or underemployed. Greece is basically bankrupt, so is Spain, and Italy is puking the living daylight out of its economy. Other countries experience something similar, which is why we call it a worldwide recession.

So if you'd like a work visa to Canada or a European country, they don't give a sh*t what you want. They want to know from you what it is you can give them that no citizen of Canada or -- respectively -- no citizen of the European Union can give them. A good answer is that you have a Master's degree in one of the hard sciences and that your work experience makes you uniquely qualified for a certain position in Canada/England/Holland/France, etc. In addition you have been offered this position by a company in said country and they are willing to spend a few thousand dollars and a few months worth of their time to sponsor you.

Now run with this, and try to figure out why it is very, very, very, very difficult to obtain a work visa to any industrialized nation, the United States included.

You apply for a visa to work in that country from the Government's immigration office.

Most of the working holidays are for citizens of the British Commonwealth, which includes Canada, New Zealand and the UK.

There aren't any short term visas for Canada, unless you have an outstanding skill, and immigration visas require work experience.

You could certainly try Quebec, if your French is excellent.

First you have to have your american passport, with a visa stamp..then go to the contractor that you will be working for to get the paper work that you will have to sign...I did when I had to go to Kuwaiti

yes. you need to go to each country's immigration service to get the necessary visa.