PureFTPd is a very nice replacement for the somewhat limited FTP server for Mac that comes with OSX. It is a free (BSD), secure, production-quality and standard-conformant FTP server. It focuses on efficiency and ease of use and has unique useful features for personal users as well as hosting providers.
A binary installer is available for both Panther and Jaguar.
To manage the ftp server Mac PureFTP Manager provides a GUI to the PureFTP server. It will ease the creation of users, viewing log files and monitoring the status of the server. PureFTP Manager is also free.
The installation of both these products were very easy, and all told, I had my Mac FTP server setup in less than 10 mintues.