Backed Up

I knew there's a solution to this but let me whine for just a minute. I'm so bummed because yesterday I'm doing a back-up in my husband's computer whole day and just as I'm about to finish it, it was cancelled, my husband might have accidentally close it. I was so disappointed. I redo it but I run out of Cds. I knew this would be fixed if I have a high memory usb drivers. I have  a 8 GB one but it wasn't enough. So I was thinking of buying a USB driver with 500GB memory, but where can I get that? or maybe I will just customized the backup. Oh well, I'll do this when I'm not that stressed anymore.