Fortran
Fortran free compilers
For a more exhaustive list of free Fortran compilers, I suggest you check http://www.thefreecountry.com/compilers/fortran.shtml
Fortran materials
Gunnar Wollan has compiled a set of documents at http://folk.uio.no/gunnarw/GEO4060/ and you can also find some of his documents at http://www.uio.no/studier/emner/matnat/geofag/GEF4510/h12/index.html
An interesting free tutorial at http://www.fortrantutorial.com/ You can skip the installation of silverfrost compilers if you already have a Fortran compiler installed on your machine or if you are using sverdrup.uio.no
The National Computational Infrastructure in Australia has class notes online for a Basic Fortran course (http://nf.nci.org.au/training/FortranBasic/) and an Advanced Fortran course (http://nf.nci.org.au/training/FortranAdvanced/).
Fortran Wiki http://fortranwiki.org/fortran/show/HomePage