For how much should I sell my Nikon D40 SLR camera?

I wanna sell my 3 year old Nikon D40.It is featured a 18-55mm lens, lens cap, body cap, original charger, battery and usb cable. I live in Norway so I think I'll get more for it than in certain other countries. How much could I sell it for?

At least around ~$150 USD

If it is in excellent condition, $350 USD

if it is in fair condition, $300 USD

if it is in poor condition, $200-250 USD

Take a look on ebay and see how much they selling for.
You should take into account the conditon of the camera on ebay compared to your one, other accesories they may have and it will usually fetch a bit more if you have the original box, the instructions and the software CD that came with it.