Snacks!
This will probably wind up as a page, as well as a post.
There are two web resources, as far as I know, that provide some lists of snacks for IBS.
This list, at tummychow.com, approaches the category of “what to eat when you can’t eat anything!”
There is a somewhat longer list at the Heather Van Vorous web site, in the forums.
Snacks, taken before your stomach is empty, seem to me to be helpful in quieting the gastro-colic reflex, that is hyper-alert and ready to be activated when your stomach is empty. I would still suggest beginning meals with soluble fiber–acacia, inulin, or guar gum–in commercial terms that’s Heather’s Organic Acacia Tummy Fiber, FiberSure, or Benefiber.