X-Plane related
http://www.xpluginsdk.org/python_interface_downloads.htm
http://www.xsquawkbox.net/xpsdk/docs/DataRefs.html
http://b58.svglobe.com/data.html
http://www.nuclearprojects.com/xplane/xplaneref.html
Open Source libraries
Useful forums, blogs, cookbooks and tutorials
https://github.com/dwtkns/gdal-cheat-sheet
https://pcjericks.github.io/py-gdalogr-cookbook/
http://www.gaia-gis.it/gaia-sins/spatialite-sql-4.3.0.html
http://geoexamples.blogspot.com.es/
http://www.toptal.com/python/computational-geometry-in-python-from-theory-to-implementation
Data
http://earthexplorer.usgs.gov/
http://openstreetmapdata.com/data/water-polygons
http://www.viewfinderpanoramas.org/dem3.html