I tried 3 different guides, and they were either outdated or they didn't work. Most of the Google results were for Ubuntu, so it didn't really apply to me because I was using Debian. I don't really know this stuff well, so when I see a guide that says to modify a directory/file that is not even in my system, I get lost. Could someone please point me to a good guide for setting up VSFTPD on Debian? I just want to setup FTP for my developer to work on my website.
Try with the official debian howto here: http://wiki.debian.org/Manual-Howto#FTPServer. It is pretty simple. VSFTP is very simple to configure.
A little more deeper guide is located here: http://www.debianhelp.co.uk/vsftpd.htm
If you want a GUI, try to install WebMin and the VSTPD module, like suggested in the last link.
To answer your comment, Doug:
You'll want to set your developer's users home directory to the /www/website.com
Then you'll lock all local users down and allow users only their home directory with:
If you only want certain users to be chroot'd:
Then edit your /etc/vsftpd.chroot_list file to include the users you want chroot'd.
By the way, here are the vsftpd config docs