How to start dog's basic training and from when ? Is there any good dog trainer ?

Hi, We have 3 month old Labrador, we want to start her training. Recently we have started taking her out for evening walk, but the only things she does, only if she does, is running behind us, but she promptly listen to her name. As soon she saw other people, she starts running towards them and when we call her name, she do not listen to that. We want her to learn all the basic commands. So pls suggest how should we start her training and from when ? Is it suggestible to take dogs to training shops ?