RichUK, some examples of good complex carbs found in breads and cereals: Whole Grain, Flax Seed Oil, etc. Don't buy any processed (white) bread, cereal, rice, spaghetti, etc. Buy whole grain, which will look brown. Simple carbs are pretty much crap for you, you'll find em in white breads (Wonder Bread, white hamburger buns, etc).
So basically:
unproccessed = whole grains/flax seed oil = good = brown
processed = crap = no nutritional value