RIYL Manga
NOVELS FORMANGA LOVERS
“5 Ancestors” series by Jeff Stone
“Vampire Hunter D” prose novels by Hideyuki Kikuchi
“Samurai Girl” series by Carrie Asai
Blue Fingers: a Ninja’s Tale by Cheryl Whitesel
Tokyo Suckerpunch by Isaac Adamson
Sandman: The Dream Hunters by Neil Gaiman (Sandman illustrated chapter book)
Kung Fu Princess: Veil of Secrets by Pamela Walker
The Kouga Ninja Scrolls by Futaro Yamada (manga “Basilisk” is based on it)
Missing In Tokyo by Graham Marks
Avalon: Circles in the Stream by Rachel Roberts (cover art and interior illustrations done in manga style)
The “Akiko” prose novels by Mark Crilley
Wandering Warrior by Da Chen
“The Edge Chronicles” by Paul Stewart
Zen and the Art of Faking It by Jordan Sonnenblick
Samurai Shortstop by Alan Gratz
Pacific Crossing by Gary Soto
Kiki Strike by Kirsten Miller
Prose Novels from publisher TOKYOPOP:
Chibi Vampire: The Novel
Full Metal Panic (novel) Vol.1
Calling You Vol.1
Chain Mail Vol.1
Mobile Suit Gundam Seed (Novel) Vol.1
CLAMP School Paranormal Investigators (Novel) Vol.1
The One I Love: Vol 1
.HACK Another Birth (Novel) Vol.1
Regular Prose Novels
Five Ancestors series (Tiger, Monkey, Snake, etc) by Jeff Stone, which are very focused on martial arts and adventure.
Sign of the Qin by L.G. Banks
Little Sister by Kara Dalkey
Truancy by Isamu Fukui. he was 15 when he wrote it and while it is text and rather lengthy it had an over the top adventure angle reminding me of National Treasure.
Across the Nightingale Floor by Lian Hearn (first in a trilogy)
The Extraordinary Adventures of Alfred Kropp by Rick Yancey
Japanese novels in translation
Moribito: Guardian of the Spirit by Nahoko Uehashi
Dragon Sword and Wind Child by Noriko Ogiwara
Light Novels (From Wikipedia: a novel with anime- or manga-style illustrations, primarily targeting teens and young adults.)
Kino No Tabi by Keiichi Shigusawa
Kamikaze Girls by Novala Takemoto
Scrapped Princess by Ichiro Sakaki
Rahxephon (started out graphic then changed to textual)
Novels that are based on manga:
Shakugan No Shana: Fight Day
Shakugan No Shana: The Girl with Fire in Her Eyes
Death Note: Another Note by Nisoisin. (you need to read the manga otherwise it's confusing)
Socrates in Love by Yoichi Katayama
Be With You by Takuji Ichikawa
Resources:
The Graphic Library by Sarah Smith