If you have to ask this question, then I'm assuming you don't have a lot of experience working on cars? If my assumption is correct, this is not a problem, it's great you want to perform this job. Just do yourself a favor, get a good repair manual and read up on this job. What seems like a fairly straight forward job can turn into a big mess if you're not prepared, so get a manual, read through the instructions, get any tools you need and get good quality parts. Leave yourself enough time to perform the job, and time to get more parts if you need them. Try http://bit.ly/alldata_repair_manuals or http://bit.ly/mitchell_repair_manuals_online and get an online repair manual subscription. These are inexpensive and good quality.
That is a huge range, if it looks like something you can do, then give it a shot. If not, I say look around some more, find a shop in the middle. Pep Boys might not have the quality of mechanic you want working on your car, that's why they can charge low prices, plus they use low quality parts. Dealers have a lot of overhead with tools, training and large facilities, so they charge more (in this case a lot more). Find a good Independent, use our directory if you need help: http://bit.ly/5Djxho
I am good with mechanics etc. But the plugs on this car are under 3 things that have to be removed, so I was hoping someone had pictures of exactly where they are, and exactly what needs to be removed. The dealer wanted $457 to change the plugs, pep boys wanted $140. Madness. LOL But yes, I will do some reading, thank you.