I have lots of King stuff, but as far as the Dark Tower series goes.
The Drawing of the Three
Wizard and Glass
The series doesn't start getting good until the fifth book! Wizard and Glass is pretty good, though... But still, if you can find the graphic novels, pick 'em up. Beautiful artwork, and they help fill in the backstory quite a bit.
SPOILER ALERT SPOILER ALERT dont read past this if you have not finished the series
I honestly CRIED when Eddie died, and i cried harder when Oy died.
and that was only 5 months ago
i bet everyone else who read the series did too.
I didn't cry, but I did whimper like the pathetic fanboy I am. :p
No book, movie or television show has actually made me cry. A few have come close. Stephen King's new book, The Cell, probably came the closest. That book is probably one of the darkest he's ever written.