Place first 3 ingredients in a blender, and process until smooth and sugar dissolves. Combine pureed pineapple mixture, coconut milk, and cream of coconut in a bowl; stir with a whisk. Cover and refrigerate until thoroughly chilled.
Pour mixture into the freezer can of an ice-cream freezer, and freeze according to the manufacturer's instructions. Spoon sorbet into a freezer-safe container; cover and freeze for 2 hours or until firm.