That file should have been installed by default, but it is in fact missing from the address book files directory then that 'could' indicate a further issue. But if only that file is missing then won't have any problems, as it's not used by OCS.
I have a blog entry that discusses the Addres Book service and the purpose of that file. If you don't plan to use RCC or Enterprise Voice and have no need to create any Normalization rules then it's no problem.