'pkg-config' is not recognized as an internal or external command,
operable program or batch file.
***
*** ExtUtils::PkgConfig requires the pkg-config utility, but it doesn'
+t
*** seem to be in your PATH.  Is it correctly installed?

[download]
The problem with your attempt is that (as the message says) you don't have a working installation of the pkg-config utility.

As it looks to me, the OP already is beyond that stage, but he doesn't seem to have a proper .pc file for the gsl library.

In reply to Re^2: Math::GSL installation on Windows XP by Anonymous Monk
in thread Math::GSL installation on Windows XP by Barnabas

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