this is a good place to start, though buyers here are notoriously cheap.
After Burner isn't a real sought-after game though it does have its fans. $150-$400 working depending on condition i think is probably fair, though with the market as depressed as it is it may be difficult to get the upper range unless you find the right buyer. more than $400 and i think you're asking to sit on it for a long time unsold.
what effects condition on a working game? rust, chipping, scratches (especially on the side art,) swelling from moisture, cigarette burns, burn-in on the monitor, non-working items like lights or stick shakers, graphic or sound errors, missing parts like buttons, back doors, bezels, etc.
eBay is an option, though the drawbacks are paying to list even if it doesn't sell and setting up shipping if it sells out of the area. craigslist is free but you have to deal with flakes and questionable people who will want to see the game at your home (a lot of folks aren't comfortable with that.)