I'll comment that there are three strategies for dealing with this issue.
1) Import filenames (they usually end up in the title or with title/author swapped) and fix the mess with S&R. I don't recommend this one.
2) Import with a regex for Add Books that correctly parses the filename into the right fields. This is what I did, but it may require you to change the regex for different filename structures.
3) Rename the files before import to a standard form, then use the same regex every time for Add Books. There are many bulk file rename tools out there, and some are specific to ebooks. If you are willing to learn to use these rename tools, this works well. Of course, the best ones use .... you guessed it ... regex
