How can I install iTunes

Ummm...download it to your computer and double click it like you would any other software...

If you want to install iTunes on your computer, see this -> http://support.apple.com/kb/vi67

You won't have to install it on your iPhone, it's on there by default. You can disable it though, from Settings > General > Restrictions.

If it isn't disabled, try finding it using Spotlight.

you have to install it on your computer and sync to your ipod the itunes app

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