iTunes Library is the key thing for every iDevice like iPhone, iPod Touch or iPod. Especially for iPhone/iPod Touch users, because their apps and games are present in iTune library. Once iTunes library erased (may be because of HDD crash or something) you will loose all your apps and their data once the iDevice synced with new iTunes library in a new HDD (And you don’t have another option).

So keep taking regular backup of iTunes library is a must for every iPhone/iPod Touch user.It also helps you to movie your iTunes library from one computer to another so that you can sync iPhone to a newer computer also.

And the entire iPhone/iPod Touch backup here also includes the backup that iTunes usually takes whenever your iPhone/iPod Touch connected to iTunes. You can also backup that ‘iTunes Backup’ to an external HDD or CD/DVD.

Backup iTunes Library to an External HDD (or) CD/DVD ::

To External HDD :

Step 1: Consolidating Your iTunes Library

To make the move as easy as possible, it’s important to make sure all of the items in your library are in one place.

1. Open iTunes Preferences:
   Mac: Choose iTunes > Preferences.
   Windows: Choose Edit > Preferences.
2. Click Advanced.
3. Make sure the option to “Copy files to iTunes Media folder when adding to library” is selected.
4. Click OK.Note: After you click OK, iTunes copies any files that are added that weren’t already in the iTunes Media folder and places the copies in the folder. The original files are left in their original locations. To save space on your hard disk, you might want to delete the original files after confirming import.
5. Choose File > Library > Organize Library.
6. Select the option to “Consolidate files.”  Note: If you recently updated to iTunes 9, you might want to consider selecting the option to “Upgrade to iTunes Media organization.” This updates the file organization of your iTunes Music folder.
   
7. Click OK.

Step 2: Copy iTunes folder to your external hard drive

To copy all the items in your iTunes library (including the iTunes Library file that holds all your playlists, playcounts, ratings, and other data) to your external hard drive, follow these steps:

1. Quit iTunes.
2. Locate your external hard drive.
   Mac: On the desktop or Finder sidebar.
   Windows: In My Computer
3. Locate your iTunes folder:
   By default, the iTunes folder is located in:
   Mac OS X: /Users/username/Music
   Windows XP: \Documents and Settings\username\My Documents\My Music\
   Windows Vista or Windows 7: \Users\username\My Music\
4. If the iTunes folder is not in the default location listed above then you can find where the iTunes folder is located by following these instructions:
   1. Open your iTunes Preferences:
      Mac: Choose iTunes > Preferences.
      Windows: Choose Edit > Preferences.
   2. Click Advanced.
   3. The location of your iTunes folder will be listed in iTunes Media folder location box, as pictured below.
5. Drag the iTunes folder to your external hard drive. This can take a while if you have a lot of items.
6. When the transfer is complete, your iTunes Library will have been successfully copied to your external hard drive.

Step 3: Restoring your iTunes Library backup

When you need to restore your backed up iTunes Library from your external hard drive to your computer, follow these steps:

1. Quit iTunes.
2. Locate your external hard drive.
   Mac: On the Desktop or Finder sidebar.
   Windows: In My Computer
3. Drag the iTunes folder (backed up earlier) from your external hard drive to whatever location you desire on your internal hard drive. It is recommended that you choose the default location for the iTunes folder, which is:
   Mac OS X: /Users/username/Music
   Windows XP: \Documents and Settings\username\My Documents\My Music\
   Windows Vista or Windows 7: \Users\username\My Music\
4. Open iTunes while holding down the Option key (Mac) or Shift key (Windows).
5. In the resulting dialog, click the Choose Library button.
   
   
6. Select the iTunes folder you just moved to the internal hard drive.
7. Click Choose.

After following these steps, iTunes will open and your iTunes Library will be restored.

Backup to Disk (CD/DVD)

To create your backup disc

1. Choose File > Library > Back up to Disc.
2. Select the option you want from the resulting dialog and click Back Up.The two options you can select from are:
   • Back up entire iTunes library and playlists
   • Back up only iTunes Store purchases

   Whichever of these two options you choose, note that you can also choose “Only back up items added or changed since last backup” to perform an incremental backup.

3. Insert a blank disc (CD or DVD) into your computer’s optical drive. iTunes will scan the disc and begin burning.
4. Note: If the disc you insert does not have enough space to hold all of the content you will be backing up, a dialog will appear asking whether you wish to backup to multiple discs. You can click Data Discs to continue.

iTunes burns the number of items that fit on one disc and then asks you to insert subsequent discs to continue burning the remaining files. Don’t eject a disc while a backup is in progress.

Restoring from a backup disc

1. Open iTunes.
2. Insert your backup disc.
3. iTunes will ask whether you want to restore from this disc. Click Restore.

Backup ‘iTunes Backup’ :

1. Copy the “Backup’” folder to an External HDD (or) CD/DVD
   Located at:
   Windows XP: \Documents and Settings\username\AppData\Roaming\Apple Computer\MobileSync\
   Windows Vista or Windows 7: \Users\username\AppData\Roaming\Apple Computer\MobileSync\
2. In future if you want to restore this data to your iPhone/iPod Touch, just copy the ‘Backup” folder to the same destination specified above.