|Very often Windows fails to assign a drive letter to an external USB storage device. When this happens, it's not visible anywhere in Explorer but it should be visible in Disk Management - and that's where you can manually assign a letter to it.|
I've never used Win2k so I'm guessing it's same as XP in this respect:
Control Panel > Admin Tools > Computer Management > Disk Management
In bottom-right pane, right-click the ribbon that doesn't have a drive letter or drive name, and is probably identified as "Raw".
Choose "Change Drive Letter & Paths"
Select a letter
Click 'next' or 'OK' (can't remember which it says)