If you're interested in lighthouses on stamps, then have a look at the blog of George Wu from Taiwan:

You'll not only find lighthouses there but also aircraft, atm collections, etc. Very nicely done.

Lighthouses are a popular thematic subject, and there's plenty of lighthouse stamps around. In Taiwan they even used to have lighthouse definitives, which could be found with a white and blue panel at the bottom.

The first British lighthouse stamps that spring to mind is a set from 1998, to commemorate the 300th anniversary of the lighting of the first Eddystone Lighthouse. It is a beautiful set and what I like very much is all the information on the stamps. We do not just have a picture of the lighthouse but there's a maritime map in the background and the bar at the bottom is actually the light pattern.