Here are some sources for fiber.
Eat fiber to protect your colon, heart, prevent diabetes, etc.
Foods with a lot of soluble fiber include:
Oatmeal
Nuts and seeds
Legumes (peas, beans, and lentils)
Apple
Pears
Strawberries
Blueberries
Foods packed with insoluble fibers include:
Whole-grain bread
Whole-grain breakfast cereals
Wheat bran
Seeds
Many vegetables, including carrots, cucumbers, zucchini, celery, and tomatoes