I live in Essex County and am also going to be looking for someone to install a dedicated line. I don't know of anyone who specializes in it. You may want to try giving CSA Audio a call as they do a lot of high end installations and probably can recommend someone.
I had a company called Tosone Electric at my house last year to do some work. They told me about wiring a guy with 10 or 12 gauge wire on a dedicated line and how they thought it was overkill. However, they didn't think he was completely nuts and did the job for him (as well as work on my house). I plan to give them a call at some point when funds permit.
