http://www.eastcoastsupercharging.com/
There are many good tuners out there, but East Coast Supercharging in Cream Ridge, NJ is my pick for one of the best.
Chris and Doug have tuned two of my cars so far, a Magna charged ls1 in a
'67 Corvette, and my current car a '69 Camaro Vert with an ls7 built by LME.
They transformed both cars. I trust them completely and would recommend them to everyone for any LS based motor. They have an outstanding reputation from years of building high powered Vettes and LS based cars.
You will be totally amazed at what they will do for your car....
Hope this helps,
Matt