To dispel the myths surrounding a much misunderstood area of interest, visit Robert Spellman's Transient Lunar Phenomena site. Another interesting related site, despite some reservations about its provenance, is NASA's Technical Report R-277 which details many sightings.
The topical subject of lunar water deposits is discussed in the NSSDC's Ice on the Moon.
Origin of the Moon is a seminal work introducing the now widely accepted theory that the Moon was created by the off-centre impact of a Mars-sized object with the proto-Earth.
More recent impacts, those of meteoroids striking the lunar surface, are explored in NASA's Explosions on the Moon.
The Moon is a rich source of folklore. Ian's Lunar Pages are an extensive resource on the various figures that different cultures see when they look at the Moon. Windows to the Universe includes an extensive section on Moon Mythology. Philip Hiscock looks at the folk history of the Blue Moon.
The centrepiece of Lunar Architecture is the detailed set of plans for a hotel on the Moon, with some very nice artwork.