websites on sale

Hello everyone! 

I found a website for sale, the earning specifics are below. A large portion of the revenues are from adsense. I'm trying to decide what to offer this person as a reasonable bid. 

ECommerce website 

1100 unique visitors per day 

$4500 per month via adsense 

$3000 per month in sales & leads 

The site is ranked 8th in MSN for a highly competitive shopping term. Yahoo also shows a very strong rating. The only negative factor seems to be that the site has either been hand banned from Google Search, or has been filtered out. Does anyone know what a site like this would be worth?