How much to change spark plugs?

I have a 1989 toyota celica st and I am looking to put it platinum spark plugs to make it last longer. Do I have to get new wires too? How much would it be for just these two?How much to change spark plugs?
platinum spark plugs can range in price anywhere from 2 dollars a piece to 8.. personally the brand u choose as your replacement would be the same as the wires.. yes the spark plugs and wires should be replaced at the same time to be able to adjust and operate the same as they wear as the years go by.. same as replacing oil filter along with new oil.. your probably looking anywhere in the range of 30 to 120 depending on how much your wanting to spendHow much to change spark plugs?
plugs'll probly be $20 and wires'll probly be another $20
go with iridium plugs, ngk makes them they are better. you do not have to replace your wires. make sure the plugs are gapped correctly.the ngk plugs are about 14-20 a plug. but worth it on the small amount of increased fuel economy. i didn't change the wires on my trans am.if you can do it yourself or ask some one to do it. you will get ripped off almost anywhere. i got quoted $285 to do the plugs in my trans am. that wasn't even counting the price of the plugs.
If you don't have any miss firing or rough idle I wouldn't worry about the plug wires just change the plugs but use some anti seize on the threads of the plugs.This keeps them from seizing in the threads in the head of the engine.But make sure you gap the plugs before installing them.And make sure of the torque when putting them in and not to over tightening them because aluminum heads with spark plug holes will strip out them threads.Use a torque wrench if you don't have one borrow one from some body if you can't buy one from a parts store and ask what the torque should be on the plugs.
I put Bosch twin electrode platinums in my Corolla 6 years ago and they're still good. I've ,since then , driven to Canada, Disneyland in Orange Co, Keystone Colorado and Vail Colorado, plus daily commute in the SanFrancisco Bay Area. I can talk about 60,000 miles on a set of platinum plugs and the original plug wires. Invest $10- $15 on those spark plugs and don't worry for the next 6 years at least.
If you haven't replaced the ignition wires, cap and rotor with Denso or NGK parts within the past 50,000 miles you'd better add that to the ';to do'; list along with Denso or NGK platinum or longer lasting iridium spark plugs. Do not attempt to second-guess or re-gap iridium spark plugs. The center electrode is so small and hard it will spall off or break if you attempt to do so.