Where should I start reading Naruto manga

[Abdula]

Yay, I win over another one. Chapter 312 would be a good place to begin. Its right after the end of previous arc where they went searching for Sasuke and its where Hidan and Kakuzu make their first appearance. It would be hard to avoid spoilers at this point since the anime doesn't stick strictly to the manga so there are a few things you'll see in a chapter that hasn't been animated yet even though the anime used something else from that very same chapter.

As for a place to download them, Mangatraders is always a start.

ch 238... thats where kakashi gaiden starts... right after sasuke and naruto fights.

I would check out the Kakashi gaiden too if I were you, because its pretty cool and its obvious its never going to be in the anime. Its 239 though.