I am looking for an open-source (command-line) tool to register and search all my (backup) drives on a file name level. I want to search for file and folder names preferably written as regular expressions or file glob patterns. The external drives contain just normal HFS and NTFS filesystems. The backups are done via direct file copy.

Requirement is that the tool compiles on OS X and works without each of the drives attached, but rather pointing me to the drive in case a drive contains a file with the pattern I searched for.

At the moment I use a hand-knit script solution with locate databases, one for each external backup drive, but this is rather cumbersome, because locate itself can accesses only one database at a time and does not contain any management system for all the indices/databases.

Are there any other tools out there for this?