Noodling is basicly reaching in and catching catfish by hand. Here is the link to a good video that not only explains just what noodling is but shows a good example.Not only have I never tried it, I don't even know what it is, lol.
If it is illegal, I would think you would definitely be fined if caught, and possibly even arrested. Wildlife and Fisheries doesn't play games when it comes to illegal activities.