Import System.Drawing.Printing namespace in your application.
Add a DropDownList and change its name to printersList and write this below code on Form's load event handler.
private void Form1_Load (object sender, System.EventArgs e)
{
foreach (String printer in PrinterSettings.InstalledPrinters)
{
printersList.Items.Add (printer.ToString());
}
}
The DropDownList will show all printers available on your network.