Boy has this subject been beaten to death. However it's not the easiest discussion to look up using either search. I'll update with some links soon.
If you're learning, you'll want to hand code some routines, but I would recommend digging into the module and seeing how it does it. It's another way to learn.
If you're writing production code, using modules is going to be faster and in all likelyhood less prone to errors. I've seen ads for Perl coders that require knowledge of CPAN.
For small tasks which is the crux of your question, which ever way works for you is the best way. What modules provide is a way for seemingly large tasks to become small.

Links to prior discussions on wheels or info on modules:
Module Reviews
Use of Modules
Finding the Correct Module
RE: Modules
Module Recommendation
Modules or lack thereof
What's your favorite module?
New Module Area?
to post, or not to post...
And the recursive link! Modules Vs. Manual Coding

Check out tye's link as well.

In reply to Re: Modules Vs. Manual Coding by lemming
in thread Modules Vs. Manual Coding by Chady

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