I've heard that these ores are actually fairly common. While I do find lots of Pyrite and such I've never found any nether uranium,diamonds,iron or anything. Am I just unlucky or are they not as common as they used to be?
if you have the mod installed they are semi rare. Much like overworld mining they are mostly found IN the rack. Just quarry some out or start digging. Just be mindful the pigman don't like people stealing their ores.