If you want to run 2 monitors off your MacBook, you will need to get
Apple MiniDVI-VGA Adapter
Matrox DoubleHead2Go
This will let you hook 2 monitors up to the DoubleHead over VGA. IIRC, the DoubleHead (and TripleHead) only let you span the externals, so instead of having 2 separate monitors, you have 1 large screen split across 2 monitors.