I'm from Wisconsin. Rusty 1990's civics, no mater what the mileage and no matter how it runs, usually go for $500-$1000. My Sedan has 250K on it, but I also rebuilt the suspension, removed the rust, had it repainted, and it has power everything including AC. That would go for about $2000 up here. With a freshly rebuilt engine I could sell it for around $2500.
There is the minor exceptions though. If somebody brings a car up here from the South, that has never seen winter, with no rust and has low miles... It will usually sell for $2000-$4000.
All I know is Southern Cars are sought after for there cleanliness. So if your car isn't clean and from the South don't expect a lot of money.
So I say anywhere from $500-$1000 for your car.
This is just my opinion based on what I see on craigslist and what I have dealt with when buying cars.