the benchmark log book system is for boilers only, usually with a fire all you get with the fire is a registration card that the installer and the householder fills in and you send it off to the fire manufacturer.
everytime an installer installs an appliance they have to register it with corgi, either by phone or over the net, corgi will then post you out an installation certificate for your records and will also then bombard you with crap trying to flog you stuff. if you don't get your certificate it means the installer hasn't bothered registering it as it costs them �4.50 to do so.. the whole process could take up to a month however so don't panic yet.