Are you accessing your FTP server from inside the LAN or from the internet? Do you have a fixed IP address and a registered domain name? If so, you don't need to configure anything. Just use ftp://<yourdomianname>.
If inside the LAN and you aren't running a DNS server, you could add an entry into the computers /etc/hosts file. Windows computers also have a hosts file.
Since you have a small LAN, you might consider installing the "dnsmasq" package. It uses it's own hosts file to provide LAN hostname/IP mappings. For external dns requests, it passes the request on to your ISPs dns server.
Another option is to use avahi. It is Linux's implementation of zeroconf in MS or Bonjour in Apple. You could use the address <hostname.local>.
At home, I use hosts files for this. It is quicker. I also use my routers dhcp server, and added static MAC to IP mappings in the routers configuration. If I need to reset the router, the IP addresses for all of my computers stay the same, so I don't need to edit all of my hosts files.