I have a lot of user logins on my machine for various tasks. When hooking into to my OS X box from another machine, this made the volume list include 7 or 8 volumes when all I wanted to make available to guests were just two of the volumes – a technical resource and my music folder.
To disable the default sharing of public directory's you need to take a trip into NetInfo Manager (in Applications/Utilties). Read the rest of the article for the details on the exact steps.
Once in NetInfo select the "users� subdirectory. You will then see all of the users enabled on your machine. You will also see other users with the names daemon, nobody, root, and unknown – leave these alone as they system defined users and do not share a Public folder.
Select the user for whom you don't want to have the Public directory available over the network. Now scroll down right to the bottom of the lower box in NetInfo and you should see an entry named "sharedDir" with a value of "Public�.
Simply authenticate NetInfo (click the lock icon and enter your admin password) and change the "Public� entry to "<no entry>� (type exactly what you see in the quotes, but don't type the quotes). Repeat this step for all users for whom you don't want public folders to be visible (NetInfo will ask you to save each modifaction as you change from user to user). Make sure that NetInfo database is saved after you have made the final change.
Stop and then resart filesharing (I don't know if this step is necessary but I have just assumed so given that creating sharepoints requires this step) and then you will find that you are only sharing the Public folders and sharepoints that you want to.
PS if there is an obvious way whithin the GUI to do this then please let me know. I can't find it ;-).

