This is two questions in one, but they're so closely related that they ought to be addressed together.
A. If I were founding a non-technological start up -- say a financial services group -- how would I go about setting up the IT side of things? As it happens, I'm a comp-sci major, and I'm far from computer ignorant. But that's beside the point-- unless I were a true guru, I still most likely wouldn't know the full range of technologies needed and how to set them up as a cohesive corporate framework -- company email, databases and servers, company website and its interaction with the servers and databases et cetera, security -- the list goes on.
When someone is starting a company that's going to need all that stuff (as many companies do), and they are computer ignorant, how do they manage it? They wouldn't even know who to hire, because they wouldn't know what skills they need. How is this done?
B. If I were starting an entirely technologically-oriented company, i.e. one which operates around a website -- let's imagine an eBay imitator -- how do I scale? For instance, Google was started by two people out of a garage with a server or two. And now obviously they have dozens of warehouses' worth of servers and databases. What's a good place to start? Just set up a personal MySQL server and work with that until you outgrow it, then hire professionals with the necessary skills to scale you up without losing any information or compromising security along the way?