going through this right now.   Yes, prongs are awesome, and much safer for your dog than a choke collar, HOWEVER! not for puppies under 6 months old.  They are babies and need to learn WRONG before being corrected for doing WRONG.
We start this the day the puppy comes home and is much like the technique described in the first couple posts.
1) we always let the pup drag the leash around the house (short nylon one). This serves two purposes 1) makes it easier to grab the puppy 2) puppy gets used to the leash and won't fight it when you go for a walk.   *ALWAYS SUPERVISE*
2)  use your happy voice because your puppy should think that walking close to you is the greatest thing on earth.
3)  don't wait until the puppy starts pulling.   Decide where you want the pup to be (not a heel position, but a nice loose leash walk, usually a foot or so away from you)   When puppy starts to put a little tension on the leash, happy voice says "hey where ya going??"  and start backing up.   The pup will look at you and you get super happy and start walking the other way.  It also helps if you are using treats in the beginning.   Give a treat for coming back to you.   Little tiny pieces can be giving while walking are the best!  
4)   keep walks with you interesting.   I wouldn't want to walk with you either if you spent the whole time on your phone or wrapped up in your MP3 player.   so don't be boring!   Talk with your dog, have him do a couple sits or downs here or there.   Change pace!  The pup is going to naturally look at you while walking, so use that to your advantage.   Say "yes!" (or use a clicker, any word you want to let the dog know that he's done something right) and give a small treat any time you catch him looking up at you.   He will learn that paying attention and being close to  you are great!  So, pay attention to him and take advantages of his natural tendencies.
5)  make sure to allow him time to be a dog.   give him a chance to sniff around, to check out all the smells, do his business etc.    Then once YOU decide to move on, then happy voice, get his attention and go!    Remember that a pup (and most larger dogs are very much pups until at least 1 yr old) has a short attention span.   Keeping it interesting will help a lot, but give him another break to sniff and mess around as a reward after he has been good.    Again, treats are useful.    
6)  be consistent!   even if you are just taking him out to potty, the same rules apply.   
Now, in the beginning you are going to be walking backwards, in circles, and talking like an over-medicated idiot a LOT and the neighbors will worry about your sanity.  But, if your like me, my neighbors already worry because I talk to my chickens, so....    
     It will be worth it in the end!
Same method works wonders for an older dog too.   Just give a slight collar pop to get his attention and the rest will follow!