The more "reputable" would be negoeskwela pero I don't really recommend hands-on training unless you are the type of person who does not the "trial and error" type of person. If you are, I am not sure if screen printing would be your cup of tea. Maybe as a business but I am not too sure as a printer.
Search youtube and there are a number of viedeo series covering the entire process of screen printing. Also search serigrafia for line table systems. Search the forum especially Philippine threads to get an idea how others do it (equipment and supplies). With the money saved, buy some inks and get your hands dirty. I doubt if your trainer will provide substantial after-seminar support anyway.
That is my view. Let's wait if others can know some trainers they can wholeheartedly recommend.
A forum community dedicated to T-shirt merchants, professionals and enthusiasts. Come join the discussion about graphics, commerce, dyes, prints, collections, guides, displays, styles, scales, equipment, accessories, reviews, classifieds, and more!