Basic guide to aerofoil selection.

Following link give a basic understanding of the aerofoil section design and how to choose them for model aircrafts.

This link gives a good insight from an experienced modeler's point of view about aerofoil and has a very good coverage of topics:
http://www.airfieldmodels.com/information_source/math_and_science_of_model_aircraft/rc_aircraft_design/plotting_airfoils/about_airfoils.htm

Description of few NACA aerofoils:
http://www.ehow.com/info_8691901_six-airfoil-designs.html

A link explaining the process of plotting an aerofoil and cutting balsa sections:
http://www.airplanesandrockets.com/resources/airfoil-plotting.htm

Journal giving insight into the flight of biological beings:
http://jeb.biologists.org/

This webpage gives general guidelines regarding the aerofoil design based on the person's experience:
http://www.nextcraft.com/aircraftdesignconcepts.html