Download iTunes 10.1 for Windows and Mac : iOS 4.2 Software Update for Free

Download the version of iTunes that you need to install Apple iOS 4.2 software update on your iPad, iPod Touch or iPhone --

Download iTunes 10.1 for Mac Download

Download iTunes 10.1 for Windows Download

How to download iOS 4.2 update
Just connect to iTunes 10.1 to get the upgrade:

With the latest firmware, you can finally enjoy multitasking, get a unified inbox, rent movies via the iTunes app and use folders to organize installed applications.
New key features via iOS 4.2 are the following:
a. AirPrint
AirPrint makes it easy to print photos, email, photos, and documents right from your iPad, iPhone, or iPod touch. A few taps is all it takes to go from viewing a file onscreen to holding a printed copy. No need to download software, no drivers to install, no cables to connect.

b. AirPlay
AirPlay lets you stream digital media wirelessly from your iPad, iPhone, and iPod touch to your AirPlay-enabled speakers and Apple TV. Watch movies and photos on a widescreen TV and play music through the best speakers in your house.

c. Find My iPad, iPhone, or iPod Touch.
Find My iPad, iPhone, or iPod touch — the MobileMe feature that helps you locate a missing Apple device and protect its data — is now free on any iPad, iPhone 4, or fourth-generation iPod touch running on iOS 4.2. Once set up, it can help you find your lost device on a map, remotely set a passcode lock, display a message on its screen, and initiate a remote data wipe. And if you eventually find your lost device, you can restore all data from your last backup.