Aerial photos on the net.

[Red Adder]

Has anyone seen http://atlas.freshlogicstudios.com/ ?
Has good UK coverage (though now about 6-7 years old outside built up areas). Uses the getmapping APs as base but has greater clarity than the county based CDs they sell, and a zoom in to 1:1,200 so you can clearly make out individual trees. Town areas may allow zoom to 1:600 (and are more up-to-date). It's excellent for do a visual check on the base map and spotting areas where searching for clearing etc may be profitable (as well as been great fun to browse around and snoop on which of you club colleagues have swimming pools etc.

Google earth does allow you to zoom in further but large areas of the country have very low resolution photographs so you don't gain anything.

[Freefall]

Excellent stuff - I hope you read my article in CompassSport as well showing other data sources. Henk (van Rossum) isn't into mapping and found some of the links too esoteric.

Getmapping is one of several providers of aerial photography in the UK. Cities Revealed stuff is used in Google Earth but is limited to main urban areas (plus quite a bit of the Peak etc). Infoterra and BlueSky don't seem to have anyhting in public domain. I can recommend the latter for stereo photos (diapositives) for PG plots.

The getmapping photos stop on the English/Scottish Border of course!