It’s probably better to have your DNS server be able to resolve ‘puppet’ to the right address, and either to have your DHCP server hand out the DNS nameserver address and search list or else (if you have static IP addresses) to have something like the following in /etc/network/interfaces.
iface eth0 inet static
dns-nameservers 192.168.3.45 192.168.8.10
But if you do want to do it via the resolvconf configuration files you will want to edit /etc/resolvconf/resolv.conf.d/base. In that file, put in your info as you would in resolv.conf.
Then tell resolvconf to regenerate resolv.conf.
sudo resolvconf -u