Three screens are better than two. Two are better than one.

Samsung displays are good. NEC is tops but pricey:

http://www.newegg.com/Product/Product.aspx?Item=N82E16824001276 (First Choice)

http://www.newegg.com/Product/Product.aspx?Item=N82E16824001273 ( Secondary Choice )

As for recommended video cards, there is only one and that the Quadro from Nvidia:

http://www.newegg.com/Product/Product.aspx?Item=N82E16814133104 ( MAX 2 Screens)

http://www.newegg.com/Product/Product.aspx?Item=N82E16814133164 ( MAX 4 Screens )