Comment 2 for bug 1437608

Two points:

1) calibre already includes a Search & Replace feature in the Bulk Edit Metadata dialog which is fully capable of doing everything you need it to do. Use search mode: regular expressions and mode: append to field.

2) calibre feature requests and general usage questions should be addressed to the official support forums at: http://www.mobileread.com/forums/forumdisplay.php?f=166

The developer does not look at questions on OS-specific bugtrackers. The people who have used calibre so much that they know all the advanced functionality and cool things you can do... don't tend to hang out here either. They hang out on the support forums.
(The Ubuntu bugtracker is on the other hand totally the right place to go to get help with getting calibre to run using a distro package.)