4l60e need help with programming...who can help?

for a few years im running a 4l60e with a pcm controller... ive never really been happy with the performance aspect of this trans. although i know that it has the capabilties to be great. ive tuned this this as best as i could and now seek someone ( shop) that can do in car tuning with me and help me get the most out of this platform. Im located in the new york area and would love to find someone who has mastered the pcm/ 4l60 trans . so can you guys point me in the right direction?
Thanks in advanced ..Pete

I've used http://pcmperformance.com, he's located in Queens, NY and very knowledgeable.