I think it's useful to think of start ups as babies. The metaphor works pretty well. Start ups and babies require lots of love to get from infancy to the toddler stage. And when it comes to starting a technology business, it's necessary to take baby steps before walking and you have to walk before running.
At Judy's Book we had a BIG vision -- I think in retrospect, perhaps too big for a start up and in retrospect I think we didn't take the necessary steps to break that BIG vision (your friends yellow pages) down into sufficiently small enough baby steps to prove out the concept before expanding the concept nationally.