if i transfer purchases to a new itunes on a diff. computer can i ever...

[Alex]

...transfer back? without loosing anything? i have itunes on one computer with all of my music and stuff.

if i transfer purchases to a new itunes on a different computer will i loose anything?

and can i ever transfer back to the orginal itunes i was using without loosing any music or apps?

 

[Unregistered]

you can find answer here

Use the Finder on the old Mac and navigate to /Library/Application Support/MobileSync/Backup - copy the contents of this folder to a USB drive or a CD-R.

Then copy the files into the same directory on the new Mac, making sure iTunes is not running - you'll end up having to restore your iPhone's info from this backup - and then right click on your iPhone in the device list and click "Restore Backup" or the equivalent option, I can't remember the exact wording.

This should prompt you to restore from a specific backup. I'm not sure if you need to set permissions for anything.

Good luck, I'm having problems restoring my contacts from my old iPhone to my new one - I went from a 4G to an 8G (1st gen iPhone) and the old contact list was from 1.1.2, when I upgraded to 2.0 I can restore all of my old Safari bookmarks, but the contacts list appears to be in a slightly different format.
you can search more information on How to transfer iTunes library and iPhone backup to new computer - Mac Forums,
and you can freedownload the software to solve the problem~http://hotdownloads.com/trialware/download/Download_j-ipod-rip.exe?item=18267-27&affiliate=575053