Hey Bésame Soy Irlandesa!
You can either try recovering the data from your old PC (take it down to a local hardware store for it), or you can try emailing Apple.
Apparently, when I Googled the problem, some people were granted access to download all their purchases again, when their hard drives crashed. Apple's policy is that all songs can be downloaded only once, since they have to pay royalties concerning the distribution of music and videos that they don't own. But, if you're lucky, just like some of the people are, you might get permission from Apple to re-download them again.
Just fire an email to customer support and tell them your situation. I'm sure they'd be glad to help.
Good luck!!
Btw, check out my blog here at www.imicrothinking.wordpress.com ! XD My goal in this month is to get a 6 figure page ranking and write 100 entries (pretty sad, I know, spending spare time doing this stuff)…but I’d be eternally grateful if you popped in from time to time and drop in a comment! Thanks !! XD