[ChemMan]

To get the rear plugs out, start by removing the strut tower brace that runs between the bolts on the strut towers. That should give you the room to reach down by the plugs. I usually find that twisting the boots until they slide around the plug and then pulling them off works best. However, it sounds like your plug wires are too far gone, so get them off the best you can and make sure to get a good quality replacement. Now as for the plugs, try and spray some penetrating fluid or WD-40 at the base of the plugs and let it soak for a few minutes. I use a spark plug socket with a 4 inch extension and a ratchet with a flexible joint the the neck. Be sure to support the head of the rachet with your other hand as you remove the plugs to prevent breaking a plug. After properly gapping the new plugs, apply some anti-sieze to the threads and install them without over-tightening. When putting the new wires on, use plenty of silicone di-electric grease inside the boots to prevent sticking, and you might want to buy some metal boot shields for the rear plugs if the old wires didn't have them.
Good Luck!