Where can i ?

Where can i get my computer reprogramd for a good price my 87 Iroc-z and whould this be worth it and give me so HP.

Really it is not worth it unless your car has some major mods doen to it like a cam change. But if you dead set on getting one I would call Ed Wright at Fastchip Performace (http://www.fastchip.com/) and get on from there. I think for just an upgrade on a chip with no Major mods he sells them for like $159.00 but special chips start from $350.00, I think.
There are others, more expensive but with your mods it is not neccesary, IMHO.

Good Luck.