Yes,all you would need is the BOB. Here's the one I use: http://www.cnc4pc.com/Store/osc/product_info.php?cPath=33&products_id=45. A BOB can be very simple and you could easily build one yourself also (see this site: http://pminmo.com/.
You would definitely need a parallel port however. It's a shame they are being eliminated in newer computers as they are the easiest output to deal with for external devices. Fortunately there are plenty of free or cheap cast-off computers available that will do a fine job. Another option is to add a PCI parallel port card although that wouldn't be an option with a netbook. In case you haven't found it yet, CNCzone.com is the most comprehensive site for all things CNC.