i am looking at a 94 z-28 i am really impressed with it but it is an auto, this will save ins. How much would a decent shift kit cost and how effective is it?

Converter will give you a better gain then a shift kit.
Check out www.LS1Speed.com for info on an aftermarket torque converter for your LT1. It will be under the "transmission" section, and you'll want to look at a converter with a stall around 2800.
Also, you'll want to buy a shift kit and trans cooler to go with it. You can expect to drop roughly .5 sec. from your 1/4 mile time with those mods alone.