No he hasnt copied a Ninjutsu yet but that's cause he really hasnt seen too many Ninjutsus. And many of the ones he has seen are bloodlimits or just too advanced for him to use. As for who would win it would definitely be sasuke he is just a better ninja overall. If Naruto's frog summoning was more reliable i would say that Naruto would win, but Sasuke has better taijutsu, more Ninjutsu, and the Sharingan. Also i believe though that naruto's stamina can give him a big edge too. His stamina is huge and it is not because of the kyuubi cause he always has a lot of chakra in battles and rarely uses the kyuubi's chakra. If he could just outlast sasuke than maybe but Sasuke is just too smart to fall for it plus Naruto is too direct to think of a plan most of the time.
I'm a firm believer in the philosophy of a ruling class. Especially since I rule
-Randal Graves, Clerks
Hyuuga Hinata FC