I have a built up 700R4 and it has a 1200 stall convertor. I was wondering what stock is and if i'm to do a cam in the range of like 2000-2500RPMS and finishing at like 5500rpms how much of a stall convertor do i need?

 

1200 stall is about what a stock converter is. If you have a power package that makes power from 200-5500 rpm that you should choose a stall speed around 1800/1900 rpm. But 1200rpm isnt to far off so you should be fine for a street car, but if you were going to the drag strip alot you might want to consider 600 rpm more for your stall.
Most cam manufacutors will reccomend what stall speed should be used with thier cams.
SSC

 

They range anywhere from what you have up to @23-2500. Here is one that is top quality and will give a stall inthe range of 2025 (rated) up to @2200 depending on your setup: GM #24202310.