1817 Views 4 Replies Latest reply: May 28, 2010 8:11 PM by edmo33
The policy on music/media purchases is that you only get one download and it's up to you to maintain a backup against loss: iTunes Store: Purchased content can be downloaded only once
The licensing of Purchased applications allows for them be downloaded over again, see this article for details: How to redownload purchased applications from the App Store
If you have an iPod that still has any of your purchases on it you'll find details in this article on how to transfer them to the computer: Copying iTunes Store purchases from your iPod or iPhone to a computer
Failing this, you could try contacting iTunes Store Customer Service and you might be able to persuade them to sanction a second free download. There have been occasional reports in the iTunes forum of this happening, however just be aware that they are not under any obligation to do so. If you click on this link it'll take you to the support/contact page, from there click on Music Purchases then the Lost or Missing Items option, from there click on "Email Us": Customer Service - iTunes Store Support
You might also want to check out these pages for future reference:
How to back up your media in iTunes
Back up your iTunes library by copying to an external hard drive
In addition to Zevoneer's excellent advice, the old PC's hard drive might be OK. The music would still be on it, and you could remove the hard drive and fit it into an external hard drive box for the new PC.
Or hire a PC shop do it for you.