As a hotel manager, I've worked with scores of Wedding Planners over the years and I'd say connections are more important than education. There is no recognized accreditation or education for becoming a Planner. Certainly a B.A. in Communications or Business would be helpful, but most Wedding Planners draw customers from their social network. It helps to have an upper middle class background, since that's the strata most clients belong to. An apprenticeship with an established meeting planner would be useful, as well.
More input:
Wedding Planning companies, offer hands on courses to teach people the role of a wedding planner and coordinator.
Wedding Planning training can also be done as a distance learning course.
Running a wedding planning business or working in one, is much more than just understanding the wedding market. You need good business knowledge, understanding of marketing, finance, book-keeping, relationship management and a drive and ambition that you cannot be taught. Basic Business Management courses will teach you a large amount of what you need to know, and then just do a one day or two day course specializing in Wedding Planning and Coordination.