The illustrations are from (top to bottom) the 1981 D&D Basic Set (Moldvay edition; art by David S. LaForce), a 1981 Games Workshop ad (artist unknown), and the 1982 French edition of the D&D Basic Set (Moldvay edition; art by Jim Holloway). I find it fascinating that the concept of role-playing was once so alien that it had to be explained with thought balloons. And I still can’t get over how awesomely bloody the GW sketch is.
If anybody knows of similar illustrations, please let me know.
UPDATE (2/11/2016): Thanks to Kai S. and Steve Wall, I’ve added two more illustrations. The first one (fourth image down) is the book club edition cover of Dicing with Dragons (1982), with art by Victoria Poyser. The second is from Dragon Warriors: Book One (1985), and the artist is Bob Harvey (see here and here). Brilliant stuff.
2 Warps to Neptune 
If you’re looking for more images like these, check out this thread at RPG Geek:
https://www.rpggeek.com/geeklist/160271/depictions-tabletop-role-playing
Bloody fantastic! Thank you.
Can’t for the life of me remember exactly where, but an OSR blog had a spoof of the first image, the joke being that the genders of the imagined PCs where swapped.
I guess we’re lucky that a girl is even represented here at the time, although it seems her PC is wearing more clothes than the male PC. That’s something. (Says the guy with two very young daughters, both of whom are currently watching Thundarr the Barbarian.)
Good stuff here. We’re actually working on a documentary that tells the story of DnD art: https://www.facebook.com/eyeofthebeholdermovie
Very cool! I’ll follow you guys on Facebook. I talk a lot about old school D&D/RPG art. Otus is my favorite.