Links

The Enthusiast's LTN Website
A huge amount of interesting and relevant information here (history, viewing facilities, map, biz-jets, based aircraft, maintenance activities, news/rumours, and an extremely comprehensive and detailed movements review). Also a very interesting collection of photos, although the quality leaves something to be desired. Unfortunately the layout can be more than a little confusing, and it's filled with a number of annoying and completely extraneous graphics and gimmicks, which just make navigation even more tricky.

AvInfo
Brief but quite comprehensive (if you see what I mean!) viewing/photography information for Luton contained on the 'UK Airport Guide' page.
The main site is mainly concerned with Birmingham airport, with other sections including a very comprehensive collection of links to worldwide airline and airport homepages, a huge listing of IATA/ICAO airline/airport codes (unfortunately searchable only by code and not by name), a large photo gallery (mostly taken at Birmingham, Manchester or Heathrow, and generally fairly good quality). Very useful resource.

Luton Airport List
A newsgroup-type mailing list, intended for members to exchange information regarding visitors, rumours, news etc. about Luton. Very useful if you live in the area.