[DMee]

Unless you really want to play with regular expressions, try the quality check plugin. It has the ability to change authors from FN LN to LN, FN and vice versa

OMG!!! Thankyou! Thankyou! Thankyou!!!

It doesn't handle badly formatted multiple authors for anyone else reading but it was a godsend!!!

As for the regexp, I don't understand what you are trying to do. Why are there colons in author names? Are you trying to reimport the books and changing the import regular expression?

The "Bulk edit metadata, use search replace" answer - if you go in there then it says multiple data gets separated by colons - the author data it showed me had e.g.

Smith, Paul : Jones, Tom

So I thought I would have to keep looping round until commas all gone using colons as delimiters for surnames..... however your answer meant I didn't :-)

Finally, and responding to your first post, if in the Author sort name algorithm tweak you set author_sort_copy_method = 'comma', then calibre will be able to cope with both FN LN and LN, FN names. Preferences -> Tweaks -> Author sort name algorithm.

Thanks for that pointer too - buried away a bit that!! However, still needed to edit the names as I use Dropbox and calibre2opds to produce a website I can browse all my books from and needed correct author names - still annoys me that some sites send back LN,FN when you ask for metadata and others don't - can't reliably select a load of books and leave it be - still have loads of checking to do might as well search individually :-(

But anyway, back to thread in question - all answered brilliantly Many Many thanks - I owe you a pint