What kind of games does he like to play? The reason I ask is because the newer games are becoming intensive in graphics demand.
And tajahem is 100% correct, stay away from refurbished unless you absolutely know the person persoanlly and has integrity.
I suggest going online and check out the Dell and HP sites. That will give you an idea of what rthey offer. Also look at what Best Buy and Circuit City have online. This will give you an idea of cost, etc.
And as tajahem suggests come back and tell us what you found. It will be important to give us the following if you can:
2. The processer unit, i.e. Intel or AMD and any and all information you can supply like speed 3.0 Ghz and so on, or name such as Athlon 64 3200+
3. The amount of memory (RAM)
4. The type of graphics card such as Nvidia 6800GT or Radeon X800.
5. Any other details you think are important.
Also, if you can supply a link that would also speed up the process. By the way, stay away from eMachines.