I'm not gonna say anything regarding a striking art or a fitness system, but even with a striking art, eventually you'll have to find a school no matter how well you learn the techniques. Nunchaku though is an EXTREMELY dangerous weapon to learn unsupervised, and padded Nunchaku just don't do the job. Careless people have been killed training with that weapon; a crazy dude in Japan attempted to practice with steel nunchaku, clogged his head and that was the end of him.
It is a great weapon to learn because, of all weapons in the east martial arts arsenal, nothing works better at developing hand eye coordination and speed. While you're making that thing fly around your hands get faster and more accurate no doubt. The only weapon that is perhaps better for that purpose, is its older, and considerably more dangerous Shaolin cousin; the three quarter staff, which is basically a tripple nunchaku, 3 sticks linked together by small chain links.
I will not direct you to a website, nor tell you were to go, instead let me try to do you a favor and warn you as to how dangerous that weapon is. Armed with a Nunchaku, its possible to crack the skull of a horse. Many Nunchaku experts from okinawa have broken even tougher materials. With a Nunchaku made out of steel, you would easily be able to kill a European knight covered head to foot in armor. The speed at which those sticks can travel is surreal.
It is an extremely dangerous weapon; without an instructor do not go near it.
Although, I would encourage you to learn it, when you find an instructor, and a good one, because its easily the best weapon for developing hand speed and coordination, second only to its more complex and dangerous Shaolin cousin.
good luck.