Go to Start > Settings > Control Panel then click Administrative Tools then Computer Management.
Under Storage in the tree diagram, click on Disk Management. Can you see the new volume there?
If you can see the volume, and it is unpartitioned and or unformatted, create a new partition using all the available space in the new drive (or as many partitions as you want), and format it as NTFS.
just locate the hard drive and right click on it and choose "Format". When done, you should be able to see your hard drive