Your network can never be too big. You probably already ask current employees and candidates whether they know anyone who might be interested in the position you're trying to fill. Go a step further, and ask them to ask their friends and acquaintances. Our office is currently working on a major project and I was hoping to get some networking contacts. There's a much larger pool of potential sources that you can take advantage of as well.
Connectors are key to an effective networking program.
If you maintain contact with them on a regular basis, you can expand your drawing pool and make yours the name that comes to mind when someone in their network might be open to a change of employment. Thirty years ago, a Harvard University psychologist, Stanley Milgram, conducted an experiment to see how many people it takes to link any two strangers. Approximately a third of the packets ultimately reached the broker. Start by asking yourself, your family, and your employees whether they know anyone who seems to know everyone. Get involved in those activities and become part of the network.