Yes, in many places around the world. In some cases it's part of anti-witchcraft laws (such as much of the Middle East); in others, there is a legal presumption that it's actually a cover for insider trading and it becomes the diviners job to prove it wasn't, a task which is often impossible; and others, such as Canada, just have the blanket prohibition.

Enforcement, at least what I saw, works the same way as practicing medicine without a license. Most of the time, done on a small scale, there's no real enforcement because it's not possible to detect when it's happening. But when it's done by a big name, or someone gets a lot of money from it, then the law can, and quite often is, used on people who admit to using divination.