Sorry about the links being down. The article is a bit old, so that was bound to happen. 🙂
This guide should help you – https://www.nomachine.com/DT09K00056

Also, I’d suggest you look into x2go as well.
I’ve tried it and found the performance to be quite nice, and setup easier than NX.
Good short tutorial here : http://lowendtalk.com/discussion/10387/tutorial-setup-x2goserver-with-xfce4-on-debian-wheezy-128m-vps