No offense intended but it sounds like your first time and no matter what you might think, you can't learn from a DVD or the internet. Find someone who knows what they are doing to help you. Heel and Sit and Here are some of the simplest things to teach these dogs and you need to get it right.
Having said that, I will tell you what I do with pups that insist on walking too far in front.
Get a lead that is long enough to have the dog at heel on a fairly tight but not strangling lead and the lead needs to be long enough to drag the ground after it goes through your hand on the side away from the dog. As you are walking with the dog at heel, twirl the long end of the lead right in front of your knee so the dog whacks itself when it gets in front of you. Spin it in a circle ith your off lead hand. Let the dog learn where the boundary is by staying in the proper position. It may take a little practice but this is how I have taught several energetic dogs to stay with me.
Don't even think e collar until you know what you are doing.