I have been separated for 15 years and can't find the husband. I want it to be done and if I am id like to know where to look it up for free

Sounds like you are married. You can look in the county clerk's office where you last lived together, and in the county where you (or he) relocated when you separated. I suppose you could contact the Vital Records office in your state, but I'm not certain whether divorces are indexed that way. Otherwise, you can start from scratch where you are now living.

If paperwork was never filed towards getting a divorce and you never took the extra steps to follow through, then I would say you are still legally married. Just because you too have not been together in 15 years does not mean "poof" you're divorced. The only thing you can do now is find a lawyer to tell you the steps you need to take to get divorced on your own. There are ways to do it if your spouse cannot be found.