Mod Ice and Fire: Dragonseeker by syrikalis

Having trouble finding dragon lairs? Look no further! Ice and Fire: Dragonseeker adds four tools, called dragonseekers, that help with tracking down dragons. At the same time, they don't make it too easy. You can confirm that a dragon is present nearby, and (with the better dragonseekers) get a rough idea of its location, but you'll have to finish the search yourself!

The basic dragonseeker is crafted with two netherite ingots and a dragon skull. It can be right-clicked to produce a tone, which is slightly higher when it detects a dragon within 150 blocks. Be careful, though- it's not infallible, and might make a mistake! It'll also pick up on dead and tamed dragons, so be sure to clear out the area you're searching in beforehand.

If you're looking for something better, take a basic dragonseeker and add a nether star in a smithing table to produce an Epic Dragonseeker. These have more durability, greater range, and a lessened error chance. They also make slightly more noise the closer you get to a dragon, letting you narrow down its position a little better, and don't pick up on dead dragons. No more interference from dragon skeletons!

Finally, once you've obtained some dragonsteel (of any type), you can craft a Legendary Dragonseeker. Once again, these have more durability and range than an Epic Dragonseeker, with a lessened error chance. They make more noise when close to a dragon, and do so more clearly than an Epic Dragonseeker, making your search even easier. They don't detect dead or tamed dragons.

The mod also adds a Creative-only Godly Dragonseeker, with a 300-block range and a 0% error chance. It'll print the exact distance to, and coordinates of, the nearest dragon in the chat.