I use a ATI Radeon HD 6870 PCI-E 16X 1GB DDR5 Video Card, Eyefinity 4..and use 2* AOC 24" wide screen monitors, which, when bought with the PC were £93 each..
I also have a spare Samsung 28" flatscreen TV which I had intended to use as the 3rd screen but am having serious doubts as to whether the particular piece of wall will take the weight where I want to position it.Otherwise it means a major move around..
I've no issues with these(AOC),but there are lots of brands on the market,have alook on Amazon,and Ebay..huge choice..
On my last PC..I had 2 *14"
flat screens and they were around £150 each possibly 7 or 8 years ago..