Changed computers I had to change computers, how do I get my music from my ipod to the new downloaded itunes? Then how do I transfer my new purchased music to my ipod?

If you bought all the music from iTunes store, once you plug in your iPod to computer, iTunes will ask you 'transfer purchases' or not. And then you can copy the purchased music from your iPod to iTunes.
This way is not work for the CD ripped music and website download music. But you can follow this step by step guide to transfer all the music from iPod to iTunes, including the non-purchases songs. It's easy to understand and works pretty well for my iPod.
http://www.ipod-transfer-copy.com/how-to-transfer-music-from-ipod-to-computer-itunes.html

iTunes is always the best tool for us to transfer music from iPod to computer or from computer to iPod, but for the situation of transferring music from iPod to new computer with iTunes is really difficult.

But there are some ways can help us to achieve it, like belows.
http://support.apple.com/kb/hT1329

http://smartphonething.blogspot.com/2012/07/how-to-transfer-music-from-ipad-to.html

http://www.leawo.com/knowledge/transfer-music-from-ipod-to-computer.html

I had TouchCopy recommended to me for that on Apple support communities, worked really well.

You've got a new computer. All your music and videos are on your iPod and you'd like to populate you new iTunes library from it. Unfortunately iTunes doesn't let you transfer anything other than your iTunes store purchases from your iPod.

To transfer all your iPod content, all your music, playlists, videos, podcasts and photos to your new iTunes library you will need to download software like TouchCopy.

Here is how to use TouchCopy

1. Download and Install TouchCopy from http://www.touchcopy.com. Downloads are free and are available for both PC and Mac.
2. Start up TouchCopy by double-clicking the TouchCopy icon on your desktop.
3. Connect your iPod or iPhone to your computer. TouchCopy may start iTunes - don't worry, TouchCopy has fixed it so that iTunes will not sync music or video with your iPod while TouchCopy is running. These changes are restored when you quit TouchCopy.
4. Select which songs you want to copy into iTunes, if you want to select all your music, select "Music" from the list on the left and click on "Copy to iTunes" button in the TouchCopy control bar.

In a similar way, you can also use TouchCopy to copy your playlists, videos, podcasts, photos, contacts, calendars, notes and iPhone SMS.

When you are satisfied that all your iPod content is safely in iTunes, use iTunes to re-sync your iPod which will enable you to add new content to it.

Here's a YouTube video that guides you through how to use TouchCopy

Unfortunately iTunes doesn't let you transfer anything other than your iTunes store purchases from your iPod.

Totransfer all your iPod content, all your music, playlists, videos,podcasts and photos to your new iTunes library you will need todownload software like TouchCopy.

Here is how to use TouchCopy

1. Download and Install TouchCopy. Downloads are free and are available for both PC and Mac.
2. Start up TouchCopy by double-clicking the TouchCopy icon on your desktop
3. Connect your iPod or iPhone to your computer. TouchCopymay start iTunes - don't worry, TouchCopy has fixed it so that iTuneswill not sync music or video with your iPod while TouchCopy is running.These changes are restored when you quit TouchCopy.
4. Now select which songs you want to copy into iTunes, if you want toselect all your music, select "Music" from the list on the left andclick on "Copy to iTunes" button in the TouchCopy control bar. In a similar way, you can also use TouchCopy to copy your playlists, videos, podcasts, photos, contacts, calendars and notes.
5. Whenyou are satisfied that all your iPod content is safely in iTunes, useiTunes to re-sync your iPod which will enable you to add new content toit.

The following simple guidance is about transfer music from old iPod to new iPod with the "Transfer Purchases" function of iTunes:

1. Plug the Old iPod into computer via the USB cable. Then launch iTunes.
2. Click "File > Device > Transfer Purchases". iTunes will automatically transfer the songs to iTunes library.
3. Plug the new iPod into computer. Then import the songs from iTunes to the new iPod.

But if you want to move the whole music library between iPods, here are better ways to help you do that:https://www.leawo.org/tutorial/how-to-transfer-music-from-old-ipod-to-new-ipod.html?=1400

first install itunes software from www.apple.com for free

Hey!
In your case, you can use an iPod Transfer tool to transfer iPod library to a new PC. You can have a try of this Wondershare iPod Tranfer, by which you can transfer iPod library to new PC, tranfer music/video from PC to iPod directly without using iTunes. You can free download it at: http://www.dvd-ripper-copy.com/ipod-video-transfer.html#181.
Hope that helps.

You could try iTunes. Certainly, there are lots of 3rd-party programs which could reach this goal efficiently. I usually use Leawo iTransfer to finish this task. Now I take it as an instance teach you how to transfer songs from an iPod to another. Download Leawo iTransfer ' Leawo iTransfer for Mac and install it.

Method 1. Transfer Music from Old iPod to New iPod(Music Purchased from iTunes Store) People can transfer music from old iPod to new iPod with iTunes or download all the songs again from iTunes Store. Speaking of iTunes, users can actually rely on the software to transfer music. If you have music backups of the old iPod in iTunes, you can easily sync the songs with the new iPod. If you don't have backups, you are also able to transfer purchased songs from the old iPod to iTunes using the "Transfer Purchases" function of iTunes. But you won't be allowed to transfer the songs from the old iPod to computer or new iPod if the songs are not got from iTunes. The following simple guidance is about transfer music from old iPod to new iPod with the "Transfer Purchases" function of iTunes:


1. Plug the Old iPod into computer via the USB cable. Then launch iTunes.
2. Click "File > Device > Transfer Purchases". iTunes will automatically transfer the songs to iTunes library.
3. Plug the new iPod into computer. Then import the songs from iTunes to the new iPod.
Method 2. Transfer Music from Old iPod to New iPod with Leawo iTransfer Run Leawo iTransfer and Connect iPods
Run Leawo iTransfer after installing it on your PC. Then connect your iPods to computer with the USB cables. The software will automatically detect your devices and show the libraries of each iPod in the left sidebar.

Select Music from the Old iPod
Click "Music" of the old iPod, and then the songs will be shown in the right part of the software. Click the transfer button (right arrow in a dark blue square) at the right bottom to transfer all the music files. Or you are allowed to hold "Ctrl" and click to choose songs, and then right click the chosen songs to "Transfer to > My New iPod".

Transfer Settings
The dialog of transfer settings comes out after clicking the transfer button or right-clicking to choose songs. Check the "Transfer to List: My New iPod" and then click "Transfer Now" to start the music transfer.

Transferring Music from Old iPod to New iPod
When the transfer begins, a dialog of transfer process will show up. The progress bar in the dialog will notice you the percentage of the music transfer. You will get all the songs in your new iPod when the transfer finishes.
For more detail, check: How to Transfer Music from Old iPod to New iPod

I recommend you am iPod to iPod/Computer/iTunes Transfer which can transfer your iPod and iPhone music, video, playlist, photos back to computer and iTunes.

If you own more than one iPods, AVCWare iPod to iPod/Computer/iTunes Transfer can simultaneously manage all the iPods in the same interface, you may transfer files among these iPods by drag-and-drop.

Hope it helps!