There are many airport de-code sites. I like this one for flexibility.
http://www8.ewebcity.com/Aircrafthan...codesearch.asp
The ICAO codes have a geographical component, E = Europe, G= Gt. Britain which would only leave 2 for the individual airport. They are confusing though - Luton always fools me, surely EGGW ought to be Europe/Gt. Britain/GatWick
