If you cannot find a "school" to train you, many shooting ranges host their own classes. Sometimes the employees are the teachers. After you find out if you are allowed to handle a firearm (not talking about buying) i would look for specific ranges and call them up asking about classes. Lots of times you can get private lessons. This may not be what you were looking for.
As for your time frame, maybe you could contact Front Sight institute. They are a fairly large organization and may have some experience with this. They host classes that are several days long. I am thankful to be in this country and i hope you're able to find a way to learn the sport.