To some extent, you're a victim of the economy right now. With your credentials I'm guessing you work as a network or systems administrator and that you've been lucky to see any kind of salary increase at all for the last three years. If recent economic forecasts have any merit (and that's always a question to which answers come only with time), your situation may improve all by itself in the next 6-12 months.
That said, the traditional way out of a more general, lower-paying job into a more specialized, better-paying job is to pick a technical specialty, pursue training and possibly certification, then make a career move from the general to the more specific. Which direction you take must factor in your particular technical interests and abilities, but good choices nowadays include information security, protocol analysis, enterprise requirements planning (ERP) packages and various database environments (where Oracle and Microsoft SQLServer offer the biggest opportunities). Once you pick a topic, a little research at a site like www.gocertify.com or www.informit.com/certification will help you decide what certs to chase. But be prepared to spend a year or two training up, certifying, finding and locating a new job/career. This can't happen much more quickly than that, unless you get extremely lucky.
This was first published in January 2004