Yeah it's probably time for a tune up. Plugs usually last 30-50k miles.
And you've never changed your fuel filter?!?! :shock: I do that about once every 20k.
Replacement plugs are pretty straight forward. They'll give you a list of names and prices. IF you want direct replacement plugs for your original plugs, get Motorcraft. Autolite's are pretty cheap in price, but I've had good luck with them in the past. As for the gap, they do come pre-gapped, but it's a good idea to check them just before you install them to make sure they're the correct distance. The only thing is, I cant remember off the top of my head what that gap is.
I would change the spark plug wires as well, but in your case you dont HAVE to. Bosch makes a pretty damn good wire IMO, but they cost a little more than others. Bosch made a big improvement on my 66, and when the time comes, I'll be putting them in my 98.
Change out your PCV Valve. It's probably functioning fine, but better safe than sorry... it's only a couple bucks anyway.
Get some additives for fluids such as Fuel Injection Cleaners, an Oil Stabalizer and if you have an Automatic, get an Automatic Trans stabalizer. To get all of this in one box, Z-Max would be my suggestion. It made a very noticable difference in my car. I know it's been shown on TV, but I used to fly a lot, and I know what the synthetic molocules used in Z-max is the same stuff that I used to put in my (my grandfathers) plane.
Check the brake fluid, check your brake pads, rotors and brake lines for any damage. Make sure your Emergency brake has any slack taken out.
Wait a minute... what year is your car? Can you get warentee work on it done?
Pick up a Chiltons Manual for your car if you havent already. It will tell you how to do lots of fun stuff with your car

.