There's plenty, some very common ones are fire eels, peacock eels, and tire track eels. You could also look into bichir species, which IMO are a lot less boring, they have the eel like appearance, but you'll find them a bit more active, rather than spending their time buried in the sand with only their head visible. All eels get gigantic, though, so you'll need at least a 55 gallon 4 foot long tank for even the smaller species of them, which get about a foot long. They're also predatory, so you wouldn't be able to keep any smaller tank mates with them, they're definitely not community tank fish.
If you don't have a gigantic tank, rather than getting a nocturnal, self burying predatory fish, you could aim for khuli loaches, which are eely looking as well, but tend to stay around 4 inches long. They eventually come out a lot during the day, and won't eat any of your fish.