Welcome to LQ and the world of doing it yourself.
Cross compiling (e.g. compiling for a mac on an x86 box) is definitely lesson 2 or above, so if possible I would compile on the mac itself. Can you get gcc on to it?
If possible, look for a package or a build script for the thing, and use that. Otherwise, the first lesson is on the configure script
when in the top source dir (e.g. /path/to/firestarter-1.03/) when you have opened the tar file.
look down for options that you want to change. I often use
./configure --prefix=/usr --libdir=/usr/lib64
You can also pass variables this way:
"CC=/path/to/my/other/compiler" "VARIABLE=assignment" ./configure --help