Here is a guide to some useful web links for London. There is a longer set of links to the top tourist attractions, most of which are not covered in this site.
Interesting links

London Necropolis
Beautiful photos of London’s cemeteries
London Photo Tours
Tour the city with a professional photographer
London Daily Photo
A photo a day from London - always interesting and fun
Ornamental Passions
A focus on the architectural details you pass every day.

Interesting links

Tired of London
One interesting thing to do every day in London
London Net
Comprehensive links to everything in London
Olympic Games 2012
London will host the Olympic Games in 2012
Town Crier
The official town crier goes hi-tech on the web