We swear by Peter's Caramel for all our caramel treats. You can purchase them in five pound loafs that will make 20-30 caramel apples. It is a smooth tasting caramel with sweet buttery flavoring and is easy to microwave and dip with. Don't make the mistake of trying to make you own caramel; you never get the exact consistency needed, costs more, and takes tons of time. Peter's caramel is widely available online or at local confectionary shops.
Good chocolate is a little tougher to track down. First stop should be your local confection shop; they are certain to have what you need. Again,we use Peter's Westchester Caps, and Guittard is very good, but there are many brands that will do. Purchase 2 pounds to make 20 chocolate apples. The chocolate comes as small quarter size wafers.
Wooden sticks need to be 5-6 inches long. You can buy them in bulk at Sam's Club, or online at the Popcorn Supply. Otherwise, buy locally or you can even use popsicle sticks, which most people have laying around from 3rd grade school projects.
Granny Smith apples are harvested once a year, around September/October, and placed in cold storage. Odds are good the apple you buy in August is nearly a year old, but you would never know becuase they store so well. Be sure to pick out apples that can stand without rolling around. Having cramel apples falling over is quite annoying.
Red Delicious are the classic apple for red candies, but I prefer the sweeter Gala apples. Either way, make sure the apple can stand on its own, and be particularly careful about any rough spot or dents. These will cause tiny air pockets that expand and make bubbles in your candy coating.