I'll need someone to back me up, but I believe you can grab a couple of AMD 7770s, and 4 Active miniDisplayPort to DVI adapters to drive 8 monitors. If the LEDs are all HDMI, you can easily pick up a bunch of DVI to HDMI cables to get them all connected. The resto of the PC doesn't have to be crazy.
Well, first up you need to define what you mean by 32" monitors. There's a big difference (potentially) between a 30" LED monitor and a 32" TV. I don't know of ANY 32" computer monitors and the 32" TV monitors come in a variety of resolutions.