Madeleine is - Mad-uh-lehn(last syllable rhymes with hen and pen)
Madeline is only mad-uh-line to me. I know two Madelines who pronounce it this way and the character from the
Madeline books and tv show was pronounced this way in the TV show. It irks me when people spell it like this and pronounce it mad-uh-lyn...this is probably due to the fact that I constantly get my name pronounced as care-oh-lyn even though I think it is fairly obvious it should be pronounced care-oh-LINE.
Madelyn is strictly mad-uh-lyn to me.