I would contact his web host and file a DCMA complaint with them. Google "DCMA" for more information. Most web providers won't even bother to see if the offending web site is doing anything illegal. They pull the site until a counter claim is filed. The person who stole your web has to respond in some way.
unless your business name is trademarked? then the person is just taking advantage of missspelling type ins and this happens all the time ..
launching a DCMA takedown is not to be done lightly as if it is not watertight it can cost you money if the other site owner can prove it's abusive ..
no-one here in fora can give legal advice ( inspite of the presence of some lawyers here as members / mods )..we can only give opinions ..IMO read the information on DMCA proceedures very carefully before deciding what to do ..