Depends on the store. You can sometimes buy it off a reel in random lengths. Not all chain stores like to do this as it makes for more difficult inventory control - look for the stores in your area that are user friendly.
You can start a store. Of course, nowadays it's easy to sell auto parts online. There are many B2B auto platforms for you to sell auto parts online.
The auto parts stores sell a kit that includes one plug boot and one contact spring, about $5.00 per cylinder. Remove coil bar, remove spark plug boot, pull contact spring out of coil terminal, push new contact spring on, install new spark plug boot, repeat steps if placing all six on a 4.0 liter, install coil bar making sure plug boots are on each spark plug correctly.
Spark plugs are avaliable from many different retailers, Pep Boys and Auto Zone both sell spark plugs. Additionally, spark plugs may be found through Sears and through automotive websites.
Napa Auto Parts is an auto parts store. They sell many parts for all types of cars. They sell engine gaskets and hoses, as well as other engine needs, but they do not sell entire engines.
NGK BP5. You can also get Bosch Supers (what I use in a Bug), but I can't find the number online. I normally just go to the auto parts store and tell them I need plugs, and they sell me the right ones.
You can sell auto parts in Houston by using craigslist.com or by visiting an auto parts recycler like A-Plaza auto parts. Search google.com or the yellow pages for auto recyclers.
Auto parts stores have permission to sell classic Cadillac parts. Cadillac parts can even be found at auto parts store websites such as AutoAnything and Caddy Daddy.
Toyota, Ford, and Mercedes sell auto parts on a national level here in the United States. They are top contenders in the car market today and sell excellent auto parts.
Chrysler recommends the plug wires they sell in their parts department.Chrysler recommends the plug wires they sell in their parts department.
At this point removal of the Cylinder head is almost your only choice. If you do manage to get is out, using an easy out and penetraiting oil and will put shavings and bad things inside the engine. If this engine is a Ford 5.4 Triton it is easy to break off spark plugs due to the design of the spark plugs. So, a broken spark plug remover kit is available that works well. Most auto parts stores can sell you the tool.
place a screwdriver inside the spark plug boot and close to, but not touching, a ground. have someone crank the vehicle as u look for the spark. Best to do it at nighttime when its dark...its also a good way to find plug leaks. they also sell an inexpensive tester at the parts store that will do this also
AutoParts Warehouse, presuming this the correct "Auto Parts" does not appear to sell used parts. There are many options for used parts, Ebay is a particularly good choice.