I have a will signed by a lawyer who is no longer in practice. How do I find out where the client files were transferred to?

I don't fully understand. if you have the original, you need nothing more. If you do not have the original and can't find it, do another one. The onlly way I see this as a problem is if you have only a copy and the will is that for a person no longer mentally able to do a new one. If that is the case, try the local bar association or the state bar association for help finding the documents. Good Luck.