Think of a name of one of the files you had in your Share folder. Search it on the computer. If you downloaded music, then search .mp3 or whichever format you normally downloaded. Check through each one to see their location. Another option, search incomplete ... might lead you to the old incomplete folder.

The old default location used to be C:\Documents and Settings\"your account name"\Shared unless you were using Windows Vista or 98. Some people chose their own preferred location.