First, check this out: http://en.wikipedia.org/wiki/Multi-monitor#Multi-display_set...

You definitely want a good video card, but you can pick up an nVidia 660 or Radeon 6770 for under $200. You'll need that should you ever do anything, like games, that requires a dedicated graphics card.

I recommend you then attach that to a Matrox TripleHead2Go: http://www.matrox.com/graphics/en/products/gxm/th2go/display...

This is what I use to mount my monitors: http://www.google.com/products/catalog?q=multi+monitor+displ... (originally posted wrong one)

Enjoy! It's awesome!