Just like citm2000 said above, this is another one of those "might as well" jobs- such as, while you're in there, might as well do the pre-cat oxygen sensors, valve cover gaskets, clean the throttle body, etc. If you have to take it off and it's old/leaking/dirty, or it's something underneath that you'll never be able to get to again, you should replace/clean/tune it now, because you don't want to have to go back in anytime soon!
When I did my plugs/wires, I also changed the rear/right valve cover gasket. First the cover didn't want to come off- it took hours of creative sideways-prying and hammer-wood-block tapping (and I did a few club3g forum searches too!) to get it to separate. Then it took me forever to chip/pry the old hardened gasket out of the old valvecover! In fact it took me so long that when I was done, I didn't do the other valvecover gasket (front/left side)... since the plenum doesn't have to come off to change it, I'll do it on a nice sunny weekend this summer.
(FYI I used the Felpro gasket/plug tube set, with a skim coat of red RTV where it goes into the valve cover, I've had zero leaks from it.)
Take plenty of pics with a digital camera before/during the job so you don't have to remember where things go. Label harnesses with masking tape like "A" to "A" and "B" to "B". Only change 1 plug/wire at a time, don't pull all 6 off! Change your distributor cap/rotor too. And like Gangsta_Man mentioned, when you take off that plenum and see 6 holes pointing down into the engine,
cover the holes with a rag so nothing falls in. Make sure you have a "torque wrench" (Sears, Harbor Freight) so you don't overtighten (and snap) the bolts OR the aluminum bolt holes, torque specs are in the Haynes manual for Eclipse and the Tearstone Factory manual online.
If you haven't worked on cars before, I do agree that your first job shouldn't be the plugs/wires- do some easy things first, like changing the air filter/pcv valve/drive belts/hoses, just to get some experience with it.