I don't use Access, as I said, but most desktop database products have security features and they should be listed in the help files - then again it is made by Microsoft
Another alternative is that you can restrict the location of the table by setting the appropriate rights for the folder where it is located. You can do this if you have admin rights to your machine and are running XP or Win2000. Otherwise, have your network admin give you access to a private folder on the the server.
If your co-workers need access to the data, but you don't want them changing anything, set the folder rights to read-only for them.
Hope this helps,
Mac