Buying components on line can often mean that you're still supporting an LBS - just not yours! There are many LBS' that sell their wares online; it saves the 12 hour drive Mike mentioned. The guys in my local are very nice and seem to know their stuff, but I wouldn't consider buying anything other than tubes, patches etc. from them as they just cannot match component prices I can find elsewhere. When they can get close, they'll get the business.