Here's a list of leveled books by grade, guided reading level and grade level.
Grade 1 - Levels C - I
Grade 2 - Levels H - M
Grade 3 - Levels L - P
Grade 4 - Levels O - T
Grade 5 - Levels S -V
Grades 6+ - Levels V - Z
Descriptions of Book Levels - (F & P) Fountas and Pinnell System.