If you want to work "in the trade"--that is, at the bench in a jewelry store environment, there are many trade schools around the country that can teach you basic repair and setting techniques. The Gemological Institute of America offers short classes that cover various aspects of benchwork, too, and community and technical colleges sometimes have jewelry technician programs that cover the same material.
The people who find success in this field are the ones who seem to have a natural affinity for working with metals and learn to work quickly and efficiently. I know successful jewelry technicians who also do blacksmithing or large metals sculpture as an outgrowth of their love of working with jewelry metals. As with any skill, it's practice and experience that makes you an expert benchman.
If you are more interested in an academic or artistic career working with metals, the usual course is to major in art metals in college and go on to complete a BFA--bachelor of fine arts--degree in art metals. The people who find success in this field are usually quite creative and in tune with the symbolic as well as the physical aspects of metals.
I know many successful academic metalsmiths who are not naturally gifted technicians but who have become wonderful artists by mastering or inventing a specific technique that became their artistic "signature"--and of course, perfecting and practicing it over many years until they became the best in the world at that particular thing.
With either course, the advice I gave you previously applies, especially the part about grounding yourself in a good knowledge of basic science and math.