I just replaced my passenger side exhaust manifold, spark plug wires and spark plugs. I started at about 11 am and finished at about 7 pm. The driver's side wasn't too bad to change the plugs and wires, but the passenger side is tough. I think it would have been worse to change the plugs and wires if I wasn't changing the exhaust manifold as well. I've worked on many different types of cars and this was by far the worst experience for changing the wires. Just take a look under the hood and see how the wires are routed, you'll understand then.
Most people recommend taking the front wheels off to change the wires and plugs but I was able to do everything from the top.
Like bbodyguy said, changing the cap and rotor is expensive. You have to take the water pump and crank pulley off to change them. At that point you might as well just change to whole distributor(Optispark) and the water pump as well.
If you are not willing to do the work yourself, be prepared to pay the price!