Remember those times when you couldn't wait for your child to start talking? Do you want to go back, if even for a second? Dealing with children who won't stop talking can be challenging, especially if they're young and don't make a lot of sense yet.
Pay attention for a while and see what kind of "talk" you're hearing. Is it the kind that comes with a lot of questions you need to answer? Some talkative children don't even care if somebody's listening -- they just want to keep talking. If your child is asking a lot of questions, spending some time answering them could help slow down the non-stop talking. Just don't be surprised if you need to answer the same question twice, as toddlers might not understand your answer the first time around.
Establish "quiet time." This should be a short period of time -- start with 15 minutes if going longer without talking is going to give your kid an anxiety attack -- in which nobody talks. Instead, find something else to do together. "No talking" doesn't mean "no voice" -- you could choose to read your child a picture book. His only job is to be quiet and listen. Or you could color, play in the yard or go for a bike ride. The only rule is "stay quiet." You could expand quiet time as your child gets used to silence.
Give your child something else to do. Could it be that Tommy has so much energy that he doesn't know what to do with it and as a result he won't stop talking? What about enrolling him in a sports or arts class? Find a local "acting class" for toddlers, where kids get to sing, perform and speak the day away. Still too much energy? Spend an hour at the playground or get a dog that loves to play Frisbee, so the dog and your child can burn energy together.
Nothing seems to be working? Talking non-stop could be a sign of a hyper child, which in turn could indicate that a child has attention deficit hyperactivity disorder. Talk to a therapist or doctor to rule out a problem.