There was a book I read a long time back, that could've been part of a series. However I don't recall the name of the book or the author's name either.
About all I remember was the general plot.
First of all, the book takes place in a castle, one that has ghosts and seems to have a will of it's own. The plot is centered around who will become king... there's a power struggle between two people and the culmination is placing their blood on the stone in the throne room. If you're not the rightful heir the stone will kill that person.
That's really about all that I remember of the book or series.