Try www.awaionline.com
This is not really a recommendation, because i've never taken any of their courses. However...I do see it advertised regularly on three of my favorite online magazines: Changing Course, Escape Artist, and International Living
Regarding 'reputable schools' as opposed to 'marketing masters' I think you need to take a look at what you're asking. If a copywriter is what you aspire to be...well it seems obvious to me that "marketing masters" is the name of the game, and therefore why not learn from the real world pros.