Now there' something for the real afficionado:
Leuchttürme Nordsee or
Svenska Fyrsällskapet (they have a well organised links page leading you, e.g., to "Lighthouse links on the web" which leads to the most interesting "Lighthouses with their own webpages"; there seem to be more lighthouses than Mudcatters with own webpages).
I'll have to stop now detracting Joe from his real task, mudcatting.

Wolfgang