Michael,
You might want to check out GPLIB from George Sexton at M.H. Software. I'm sorry but I don't have the web site address in front of me, but you can find it easily with an Infoseek search on 'GPLIB'.
'GPLIB' allows you quite a bit of access into the Netware API, so you could put together some kind of system that relies on NDS information to provide what a particular user has access to. However, as with most applications the user would probably still need access to all of the files at the raw file level. Thus a user could circumvent the entire system by looking at a file directly with a development copy of VFP (or any one of 1000 other tools).
Regards,
Michael