Choosing a Display
The choice of display boils down to Cathode Ray Tube (CRT) or Liquid Crystal Display (LCD). The better CRT displays have mostly been discontinued and are hard to come by now, although there are a few good quality CRT displays such as the Sony Artisan that you may find in use. But apart from that, your choices these days are restricted to LCD displays, of which the quality can vary greatly.
There are different classes of LCD displays starting with budget-priced models and those on laptop computers, to large-screen professional LCD displays offering a high degree of color accuracy and wide color gamuts, such as the Eizo ColorEdge display. My personal favorites have been the Apple Cinema display series. These days, I do most of my color work using an Apple 30-inch screen because I find the large screen area more comfortable to work with, and it is also easy to calibrate and profile.
As with all things in life, you get what you pay for. Since the monitor is what you will spend all your time looking at when making critical image adjustments, it is as pointless to cut corners when choosing a display for the computer as it is to scrimp on buying anything but the best lenses for your camera.