tar xvfz gf-3.0.tgz
    cd gf-3.0
    # alternative 1:
    runghc Setup configure
    runghc Setup build
    runghc Setup install
    # alternative 2:
    make
    make install
Mac binary: gunzip and put somewhere on your path.
Linux: tar xvfz in /
Windows: unzip in c:\
Compiled library: tar xvfz in some DIR and point the variable GF_LIB_PATH to DIR/lib.
Source package: tar xvfz somewhere and compile as follows:
    tar xvfz gf-3.0.tgz
    cd gf-3.0
    # alternative 1:
    runghc Setup configure
    runghc Setup build
    runghc Setup install
    # alternative 2:
    make
    make install