Bill, all 386 Pokemon ARE in Ruby and Sapphire. Well, they're all
programmed in there, anyways, but most of the originals are locked, and not available in the main game (or in other words, initially obtainable). Don't believe me? Check out
this page to see all of the original Pokemon with their Ruby and Sapphire sprites, as made available by people who hacked into the actual ROM. The new Ruby and Sapphire information, such as their traits, new pokedexes, movesets, and so forth are also available somewhere on the Internet, once again as provided by the hackers.
Pokemaniacs have known all of this for a while, though, and now it's only a question of how to unlock these Pokemon on your Ruby and Sapphire games. Pokemon Box, I think, may be the answer.