I'm sorry to have to be blunt here.
If I was interviewing someone for a potential job and he or she had been writing CGI applications for 5 years without seriously investigating what resources were available to do things better, then I would recommend against hiring. Here is why:
- That person will be unfamiliar with every module that is at my workplace. That would be a long learning curve.
- That learning curve is likely to be slow - you need to learn how to pick up and evaluate new modules. If you haven't learned, then you are unlikely to be familiar with the necessary techniques when you first encounter them.
- I would automatically distrust his or her design sense. The heart of good design is a tendency to question whether problems that come up could be solved in a better way, and searching for what that might be. This is not consistent with sinking into a rut and staying there for 5 years.
- I would be inclined towards distrusting his or her skill level. There is a difference between 5 years of experience, and one year of experience repeated 5 times. This sounds like the latter happened.
Furthermore if the roles were reversed and I was the one interviewing for the job, huge red flags would go off for me, and I would be strongly inclined against working there. Mainly because of what it says about the work environment and my likely interactions with co-workers there. Having to deal with the consequences of what I know are basic mistakes repeated over and over again is painful. Giving a remedial education to people who think that they don't need it is hardly my idea of fun either. That goes double if they are smug about their lackings, and/or have support from management.
Sorry, but this is my reaction. Whether or not you care about it is your decision.
If you do care, then a few places to start are by looking into source control systems, playing around with Class::DBI, or searching for templating systems. Or you could read a book, either Perl-specific (O'Reilly has a pretty good library, add in TheConway's OO Perl if you want), or more general (Code Complete is a good start).
Oh, and as pointed out by Abigail-II, start calling the language Perl.