How can I remove shellac that spilled over things in my tool/work room?

[Tom]

A can of shellac sitting on a shelf started leaking and is now on a leather stool, plastic work horse's and etc. Due to my not being aware of this happening, the shellac is now dried. What course, if any, may be taken to remove it. Name of the shellac that spilled: Zinsser Bulls Eye Shellac

[homeowners]

The cleaning will have to be different for different surfaces. Shellac can be dissolved by alcohol or ammonia with water (or other similar strong alkaline solution)  and they can have different effect on the material of the item you clean. By the way, none are particularly pleasant chemicals so anything you clean will have to be brought outside first. Pretty much all are toxic in high concentrations. 

Ammonia is not flammable but very corrosive, so can't be used on metals. Alcohol (isopropyl of ethyl) is safe for metals but is flammable and, in addition to that, can dissolve most color dies in porous materials. For example, I would be extremely careful with that leather stool and alcohol because alcohol may discolor the leather but, at the same time, if the stool has metal parts, especially chromed, they can be damaged by ammonia. 

You obviously don't have to completely dissolve the shellac, just softening it and then wiping off would work. So, I think you can try different concentrations, start with more diluted and  progress to more concentrated for the spots that could not be cleaned.

It sounds like quite a bit of work, no matter how you approach it, so I wish you best of luck!