There are many resources online that offer printable graphic organizers. Some of them are:

EdHelper.com

Education Place

TeacherVision 

Teachnology

Another option is simply to click the organizer you want:

Venn Diagram - For basic compare/contrast of two characters or story elements

Venn Diagram (Triple) - For compare/contrast of three characters or story elements

Character Analysis Pyramid - To build an understanding of a main character