I got some bran crackers at Whole Foods, very high in fiber. They are called GG crackers and I'm not sure they are in all the WF stores. They're very filling, have 12 calories in a cracker, and lots of fiber (at least 5 grams of fiber in a cracker).
They're available on Amazon, but cheaper there. Pretty tasteless but OK when you spread them with peanut butter.
Another option is just adding some oat bran or wheat bran to your morning cereal. Count that in fitday, along with your cereal, eat fresh fruits and vegetables and you've got a good start, fiber-wise.
I really do eat those crackers and my daily fiber is often over 50 grams.