Alas, we do not have a graduate program; it's a weird quirk of our history as a program. (I'm at a Boston-area university.) What happens is that a number of graduate students in other departments often wind up essentially with specialties in folklore, but in their own depts. Our program itself is made up mostly of faculty with appointments in other depts -- like Anthro, Religion, English, German, Celtic, etc. -- whose own specialties are really folkloric in nature, so the courses they teach count for our program.

Indiana University and the Univ. of Missouri have two of the best Folklore graduate programs in the U.S. A number of other places have graduate programs that can specialize in folkloric studies, within other disciplines. This page is a good place to survey them:

http://www.loc.gov/folklife/source/list_highered.php