best choice FTP Server

[admin]

Hope this make sense.

Looking for the best way for people to manage their websites.  Well I am
hosting a bunch of virtually hosted websites based on hostname (single IP
machine).  I am needing to set up many ftponly accounts (no shell access)
which will drop users into the proper directory depending on which username is
in use.  Is there a way to do host based ftp? I also want to lockout users
from logging into the ftp site who have shell acounts but do not need access
to update their websites via ftp.  what is the best software alternative out
there for me?  

- Noah