I've heard Kakashi hooks up with Iruka.
Sasuke and Karin have ****ed.
Probably Shikamaru and Temari, although their exact relationship is always ambiguous.
Yahiko and Konan definitely screwed. Nagato stood outside their door, and is a Sensor type.
Jiraiya definitely got laid more than once.
Tsunade is not a virgin.
Obito wouldn't be a virgin, but he doesn't care about this world. In the world he intends to create, all past blueballing will have no value, and it'll be a world of only getting laid. He and Kakashi will finally be able to do Rin at the same time, because the Sharingan works best as a pair.
Madara was a virgin, but all he ever loved was Hashirama. He loved Hashirama so much, he even lost his genetalia in an unfortunate ninja cell implanting accident.
Orochimaru is a virgin, but he's transferred into bodies that have ****ed chicks and dudes. Once he steals Sasuke's body, he'll have ****ed Karin, and will again.
Zabuza and Haku, it's obvious.
Minato and Kushina, but only once. They don't call him the fastest ninja in the world for nothing, and Kushina has the stamina of ten women.
Guy obviously ****ed Lee's mom and that's why Lee has those brows. It's not in the plot because it doesn't matter.
Zetsu is asexual but odds are he transformed into some chick's husband and ****ed her good while he was out fighting.
Naruto will always be a virgin until he rescues Sasuke. After all, how can he be Hokage if he can't even save one friend?