This thread is over a year old, but here's how I would do it.
Once you have VSFTP installed:
1. edit "/etc/vsftp.conf" as the root user, changing/setting these options:
2. create "/etc/vsftpd.userlist" and add the desired usernames to the file, each one on a separate line.
3. then use adduser to create unix users on the server:
sudo nano /etc/vsftpd.userlist
replacing <username> with the name of the FTP user (which must match what you included in the /etc/vsftpd.userlist file). There is a series of questions, which are not too important, although including the user's real name can be useful in the future.
sudo adduser --home /path/to/users/ftp/dir --shell /usr/sbin/nologin <username>
4. finally, restart vsftpd:
And then test it!
sudo service vsftp restart