As others have already reported, the Dizzy Dragon website now includes the most awesome online random dungeon generator I've ever seen. Not only does it combine the monsters and treasures from the Moldvay/Cook/Marsh Basic/Expert books with the dungeon dressing details from the AD&D Dungeon Masters Guide, but, even more impressively, it creates really good dungeon maps. I mean really good. Most random dungeon generators produce uninspired maps with only a handful of rooms and a very obvious "path" through them. That's not the case, where the maps are sprawling, with dozens of rooms, secret doors, winding corridors, pools, crevasses, sections of cavern, and much more. It's frankly amazing.
Check it out. Please.