Open the Registry Editor click on the Start button on your taskbar, then click on Run and type "regedit" and click on OK to start the regedit utility.

Expand HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ Windows\CurrentVersion\Explorer

If one doesn't already exist, create a new key called "DriveIcons". Under this key, create a new key with the letter of your drive.

I.e. C for your C:\ drive.
To change the icon for that drive, create a key inside that one called "DefaultIcon" and set the path of (Default) to the location of your icon.
eg C:\DefaultIcon\
then (Default) = D:\Documents\C Drive Icon.ico
To change the name of that drive, create a key in the drive letter one (eg C:\) called "DefaultLabel" and set the (Default) to what you want the drive to be called.