Illustrator Jan Brett has some adorable Halloween coloring page printables on her website, including:

• Hedgie Carves a Halloween Pumpkin Coloring Page
• Hedgie's Halloween Costumes Coloring Page
• Hedgie as a Pirate Coloring Page
• Halloween Place Mat
• Happy Halloween Bookmarks

Jan Brett is the renown Illustrator of The Mitten, The Umbrella, The Three Snow Bears, Honey... Honey... Lion! and many others.  More info on her amazing website is available here.