A barebone system is going to be a case with a motherboard and a PSU. Not alot else unless they state that extras are added. It will only tell you what is compatible with it, such as what CPU,memory drives etc...
oh ok i am thinking of getting this one and taking my old desktop cpu and putting it in http://usa.asus.com/products/desktop/pundit-r/overview.htm thanx
good luck if have to get a new motherboard to fit that case if that board craps out as it is not a standard motherboard.
You are going to be very limited with what you can do with this in the future. It only has PCI slots for a start, the PSU is only 200W. As long as you don't intend to add a tv card or similar you will be okay. Asus don't really make crap, so it will okay. You also should not be paying over aboout £100 for this.