ok, you can see it, thats a good start :-P
you could try this: (im assuming you know all about mounting drives.. you will have to be root
mkdir /mnt/drive <- somewhere to mount it
mount /dev/sda1 /mnt/drive
if that works, you can then get to the files in /mnt/drive. you will need to be root to write to it. If it works all fine, we can move onto giving the user access.