However, I don't know how to install external libraries - e.g. libgd - in a way that my new perl can find them

I think most people attack this the other way around - they build their perl in such a way that it automatically finds the existing external libraries by, eg, ensuring that the path to these external libraries is built into $Config{libpth}. (Running perl -V:libpth will print out the existing value of $Config{libpth}.)
Not sure how you'd achieve that with perlbrew - I build perl often enough, but I don't use perlbrew (and I doubt that I ever will).

Another option that should work if you're using a gcc compiler is to set a couple of environment variables: 
export CPATH=/opt/local/include:$CPATH
export LIBRARY_PATH=/opt/local/lib:$LIBRARY_PATH

[download]
Does that second option work for you ?

Cheers,
Rob

In reply to Re: Installing external libraries for perlbrew perl by syphilis
in thread Installing external libraries for perlbrew perl by bangor

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