To install the GeoIP C library, go to
  http://www.maxmind.com/app/c

Note that Geo::IP 1.13 requires GeoIP C 1.1.2 or higher

To install the Perl XS wrapper, run

  perl Makefile.PL
  make
  make test
  make install

(If you get a "libGeoIP.so.1: cannot open shared object  No such file or
directory" error, add /usr/local/lib to /etc/ld.so.conf then run
/sbin/ldconfig /etc/ld.so.conf     )