I stripped a small cabinet but it has a bad stain in it, like something had been spilled on it. How far can I sand it down? Or is there something I could put on it to “take the stain out”? I really don’t want to have to paint it because I like the wood look better.
You don't want to sand too much. This will leave a noticeable depression. Try sanding the area, expanding out to lesson the effect. Another way to remove the stain is to use chemicals. Wood bleach or two part peroxide, available at many paint stores, could remove most of the stain.
Using chemicals can be problematic. They will change the color of the wood, lighten it. Most likely some of the stain will remain.