2) The Girl From the Well by Rin Chupeco. I've mentioned before that Chupeco is one of the most oddly brilliant writers I've read. This is well-shown in her most famous book, a YA horror about a Japanese-American boy with a murderous ghost attached to him. It's reminiscent of The Ring, but a little more cultural and less gory.
3) Shutter by Courtney Alameda. This book also features monster hunters; in this case, a tough-but-tragic teen girl who captures ghosts on film with the help of her trusty teammates, all part of a long legacy of hunters. It's intriguing, engaging, and at times, heartbreaking.