Monitor:Asus VE278Q 27.0" Monitor ($289.99 @ Amazon) Total: $289.99 (Prices include shipping, taxes, and discounts when available.)
One of the highest rated monitors out there now.
Alternatively you can save a bit and go with this: Monitor:Asus VH236H 23.0" Monitor ($157.58 @ Newegg) Total: $157.58 (Prices include shipping, taxes, and discounts when available.)