The first thing you'll need is a correctly fitted harness. I can PM you an address for Missy Villines. She's in Missouri, but she makes the best harnesses. Her prices are comparable w/other manufacturers.
Other than that, all you need to start out are some lengths of chain, that your dog will drag, and a nice grassy place to work your dog.
Believe it or not, you'll be teaching your dog to pull calmly, evenly, and patiently. It's not about running down the track, because when the weight gets heavy, your dog needs to be willing to work slowly.