How to add songs from your computer to ITunes
Step 1
Turn on your computer. Launch iTunes. You can do this by clicking on the iTunes icon on your desktop.
·Step 2
Select the Files tab. Next, select the Add to Library tab.
·Step 3
Locate the file, folder or volume you wish to include and click Open. iTunes will choose which files it can play and add them to your library. You can also drag your selections to the iTunes icon in the Windows Start menu or the Mac OS X's Dock or into iTunes main window.
·Step 4
Play a song. To play the song, click on the title of the song and then click Play

Also refer to: How to transfer songs from Itunes to IPod
Step 1
The first thing you want to do is connect your iPod to your computer via the white USB cable.

WARNING: If iTunes opens and asks you if you would like to sync up your ipod click NO
Step 2
After your iPod is connected, open My Computer, or just Computer from the start menu and look for the ipod drive. It should be in the (F drive. You will see the iPod logo in the listing of disk drives.
Step 3

If you are using Windows vista: Open the iPod drive and click on ORGANIZE. Then folder and search options tab. Then View and Show hidden files and folders.

If you are using Windows XP, open the iPod drive and click tools then Folder options then View tab then click show hidden files and folder. Finally click Apply.
Step 4
Now you should have a new folder called ipod_control. Open that folder up and you should see the following: Calendar, Contacts, ipod_control, notes, photos, etc.. If you are trying to save all of your music then the ipod_control folder is the only one you need to worry about.
Step 5

Open the ipod_control folder then open the music folder. Copy each one of those folders (should look similar to these: F00, F01 ...) onto your computer.

You can do this by creating a new folder on your desktop and dragging the files into the folder.
Step 6
Open itunes and insert the new folder you created on your computer's desktop into: library ---> Music
Step 7
You can now sync your ipod to this new computer with out losing all of your music.

http://support.apple.com/kb/ht1329 (Apple link for further reference)


If you can't download itunes itself please check your Internet Explorer setting >

1.Allow popup
2. Allow Active x to run


Also check your antivirus program setting if its blocking any downloads.. you can also download itunes from another pc and install it on your one..


cheers