I use a slightly different technique for getting the watershy dogs in.
I use three different ways. The first is to get a reliable older dog that is good with the pups. I start throwing retrieves for the older dog and let the pup follow the older dog around. The pup will often times follow the older dog out for the retrieve. They seem to trust the more mature dog that all is fine in the water and it is safe. Do this with a pup that loves to wrestle and chase an older dog. They will usually forget there fear of the water. Another way is to get a pigeon tie its wing down and toss it out just barely beyond the pups reach. A live pigeon will cure a watershy pup almost every time. Another way is to get you and a couple of your kids or borrow your neighbors children. Go down to the local pond and jump in. Splash around, make lots of racket, lots of laughing and excitement. The pup will be beside himself with wanting to join you and will come in like its tail is on fire. One of these three techniques should do it. Like the people above said, never force the dog to go in. Once in the water
try to make it as positive expierience as possible. No difficult retrieves yet, and no heavy duty horseplay.

Use a Big Lead to shoot them
were they aint.