updatedb: fatal error: load_file: Could not open file: /etc/updatedb.conf: No such file or directory

Simple fix for this error, you need an /etc/updatedb.conf file, so:
sudo vim /etc/updatedb.con
and paste this in:
PRUNE_BIND_MOUNTS="yes"PRUNEPATHS="/tmp /var/spool /media"PRUNEFS="NFS nfs nfs4 rpc_pipefs afs binfmt_misc proc smbfs autofs iso9660 ncpfs coda devpts ftpfs devfs mfs shfs sysfs cifs lustre_lite tmpfs usbfs udf"