in reply to
What book would be valuable to someone self-taught?
Learn a New Language
That's the best advice I can give you. Perl is a great, powerful language, don't get me wrong there. But you don't have to be stuck with Perl forever. There are not many ways to take a step up from Perl, as it truly is extremely powerful. But taking a step down will only help you.
You can learn C or C++ as they are great languages, but are pretty limited compared to Perl. Because Perl has most of the functions that C uses, this will help you when you use Perl, as I can almost guarantee you have not used everything Perl has to offer.
You could also shift to another language that is comparable to Perl, such as Python. I have never used Python before, but I've heard it is extremely powerful and pretty cool (not as cool as Perl of course).
As for the books...
- Pragmatic Programmer
- Programming Pearls