In a small IT department (<5), typically in a small company (<100), it realy doesn't matter what title is given to the guy in charge of IT. Still, the most appropriate title is IT Manager, or possible, if he's been there for a while, Director. However, the Director is title is mostly honorary, or necessary for political reasons.
When you start getting into larger companies with multiple IT groups, then typcially each group will have its own Manager which reports to the Director of IT. This group is likely to report the Chief Financial Office, or whatever title is given to the person who manages the accounting side. If the politics play out differently, they could report to the President and/or CEO.
At the enterprise level, where there are at least dozens of employees in IT, among many different departments, usually requiring multiple Directors to manage the Managers, then there is likely also an executive. This will either be a Vice-President of Technology, who will report to the CFO, or possibly the CEO, or an actual Chief Information Officer. They may also have a Chief Technology Officer, and a Chief Security Officer, and software development firms will usually have a Chief Software Architect (see Microsoft).
At this level, the responsibitly of the manager in an IT group is to manage the personel in that specific group. A Director manages the managers and handles budgetary duties. An executive or a "C" type is supposed to take the most strategic view of the organization, clearly understand the business requirements and facilitate interaction with the other departments. They'll set the agenda for strategic projects and technologies and significantly influence the selection of vendors.
Note that it is only in the largest organizations that it gets broken out like this. You get the specialization because there are so many people. In the smaller organizations, each person has to perform multiple types of duties which are usually split out in the larger organizations. So a small company's IT manager will have to do things that a larger company would only use a CIO for just because they are the only person to do them.