I will post links to websites that sell some of this gear as well as descriptions of what you should look for in the way of quality.
Metal Detectors
Metal detectors are perhaps the most common tool in the treasure hunter's arsenal. They enable one to find hidden valuable with relative ease. Built with the average person in mind, they require very little strenuous activity to operate and can help you to find hidden treasures with out having to resort to exploratory digging. The downside to these are that depending on the model, they can get fairly expensive. There are many dealers that cater specifically to the treasure hunting community that are very helpful.