These are brilliant, here's some of the classics...
"Lobby Cards made their first appearance in the early 1910s around the same time that Charlie Chaplin was breaking into motion pictures. The earliest Silent-era lobby cards were often nothing more than black and white or duotone stills. These were eventually replaced by hand-tinted scenes, and by the 1920s most studios were producing full-color lobby cards. The collectibility value of lobby cards is influenced by several factors, the most important of which is the graphic appeal of the card itself. A lobby card featuring a closeup of the main actors, or the monster, or depicting a key scene, is much more desirable than a card showing only a distant shot of the stars, or a “dead” card featuring no stars at all. The importance or popularity of the film is another key factor in determining a lobby card’s value." http://www.filmposters.com/lobby-cards/lobby-cards.asp
You can buy them here: http://www.morbidmonster.com/LobbyCards/index.html and there's lots more to look at here: http://www.lobbycardinvasion.com
Image gallery order:
HG Wells Things to Come (1936)
Earth vs. the Flying Saucers (1956)
Barbarella (1968)
Attack of the 50ft Woman (1958)
Batman (1966)
Creature from the Black Lagoon (1954)
The Curse of the Werewolf (1961)
The Day the Earth Stood Still (1951)
Fantastic Voyage (1966)
Godzilla (1956)
Forbidden Planet (1956)
It Came From Beneath the Sea (1955)
Invasion of the saucer men (1957)
The Thing (1951)
This Island earth (1954)
13 Ghosts (1960)
The Time Machine (1960)
When Worlds Collide (1951)
War of the Worlds (1953)
2001 (1968)