An important aspect of a monitor that a lot of people ignore is the panel type. You have IPS, MVA, PVA, and TN monitors with various subtypes as well. TN is the common type that sells the most because of the price and it's response time can't be beat but it is also really bad at color reproduction. Sadly most companies don't advertise what panel type a monitor is, so you have to go by specs or just google the model number.
Dell often has a deal on the
2209WA which is probably the best 22inch LCD on the market right now for the price. I managed to pick one up for about $200 and I couldn't be happier with it. It's an E-IPS panel so you get great color reproduction but still have a good response time.
Another good tip for anyone in the market for a new monitor is to watch out for bad monitor return policies. Newegg for example, requires more than 8 dead pixels before you can return it.