Airlift
The FAA aircraft dispatchers courses are recognised and convenient - but do not assume you will be getting the
best. Although, a useful qualification to have, it is largely US/FAA specific and does not cover 'rest of the world' ICAO based systems. The syllabus is also not as comprehensive in technical subjects as the ICAO 7192 D3 requirements; it is important to know that a US dispatcher continues his/her training once they join an airline. As someone without previous ops expereince, you would need to continue your studies to cover the gaps in the FAA dispatchers courses for work in Europe. But if you do want to do the course- Sheffield has been recommended to me by former students on many occasions.
The link below leads you to an interesting 2007 work by Andreas Cordes for his MSc at London City, it'll give you a feel for things and has an outline of ops officer/dispatcher training- in particular his comments on page 57.
At the end of the document the 7192 D3 syllabus is detailed and a sample course from LH and some other course suggestions.
http://www.eufalda.org/Download/Dispatch%20Study.pdf