I don't see why anyone would want those 'square' monitors these days, mostly everything i've seen is now widescreen anyway?
I have a 22" Widescreen Samsung and I love it for my graphic design and it's great for my photo viewing/editing as well. It's run at 1680x1050, so it's pretty high resolution. I'm looking at buying another one so I can put tools etc on the secondary one.
You could look into the monitors that you can tilt 90degrees so you can use it in portrait mode (the screen will turn when you turn the monitor).