Boot from the Ununtu CD again. You should be able to see both the external drive and the Windows drive so that you can copy the documents back.
I tried that, it seemed logical. However, now Ubuntu doesn't see the drive either. Drive is visible in device manager, and disk manager in both windows xp and 7, but read as unallocated drive. I cannot assign the drive a letter. Recovery software is not seeing the drive either. I think I can reformat using disk manager, but I don't want to loose almost 500g of data.
Thanks for your help.