It's easy. When we lived in Australia, my husband hooked me up a 19 inch flatscreen to my Mac laptop. You will probably want a separate keyboard, too, otherwise it will be awkward. Any monitor will do. I think the one I had was an HP.
You just need the display-port adapter to hook up any other monitor you want. Depending on how old your macbook pro is, it may have a dvi port on it instead of a display-port or mini display-port.
I have hooked up mine to TV's and large monitors, works great! You can always get an Apple Cinema Display