before an early mornging ride, I find that a breakfast bar or a bowl of cereal like untoasted muesli is pretty good. Muesli has a low GI and therefore provides a slow steady release of energy over a couple of hours - if you add some fruit like peaches, this is high GI and will give you a quick energy boost to get you started until the muesli's energy kicks in. How much you eat depends on how far you're going, ie a big bowl of cereal is great if you'll be much more than 2hrs, if its only a 1hr ride fuit might be ok.

Be careful, I know some people say that if they eat dairy before a ride they get stomach cramps, but not me. If the ride is after work have a good lunch with either bread rolls , rice or pasta and follow it up with a muffin or something just before your ride. After a ride I'm a firm believer in lots of water (to replace lost fluids) and a 1 slice of bread honey sandwhich or fruit before you shower. This gives you the energy to get through your shower and whatever until your next meal, because after a ride of 2 or more hours your energy supplies will be low. Don't forget fruit, snacks or money on rides of 3hrs or longer. Experiment, you'll quickly learn what your body doesn't want you to eat just before a ride.