I cant really tell, the 9700 has very old tech inside(in technology age).
Your best bet is to see what others are selling for on ebay.
But you should be able to get around/atleat 1000$ maybe a little more just because its a sexy AW laptop. But there are brand new 17" laptops from say HP that blow the doors off of it feature and spec wise(save for the grfx/sli potential) but its already getting hard to find grfx cards for that unit.
I would say if you can get anything north of 1000 consider yourself lucky, and even if you have to go south of 1000 just to move it, Id still jump on the opportunity because its losing value every day, at least that way you can get out from under it.