Computer pricing help?

I want to sell my desktop but I don't know for how much. It has 1Gb ram , 2.0 processor , 80 Gb hard drive , and its an emachine with an up graded graphics card. It will include a 15 inch flat screen monitor and a wired laser mouse and a Satek Eclipse II keyboard.(heres the link for the keyboard)http://www.frozencpu.com/products/5351/kbd-81/Saitek_Eclipse_II_Illuminated_Key_and_Backlit_Keyboard_PK02AU.html?tl=c51s377b106&id=mJokNfFS