You're not going to get a super deal unless you get a bunch of cars from one area to go to one of their tuners of which many work out of their home garage. The other option is to get a group of people to commit, remove their ECU's and ship them to a tuner for a group discount. Good luck on the second option.

As suggested, do a search, all of this has been hashed over many many times. Several group buys have been tried in the past, but they just feel through. To my knowledge most people did it on their own at a tuner near them and have been very happy with Upsolute.