Charmander made it all the way to Charizard, and then decided to stay in Charizard Valley with a female Charizard. last time I remember him making an appearance was right before Ash went to Hoenn, I think it was and he fought Blaziken, the first of the Ruby/Sapphire/Emerald version Pokemon we see in the show if I recall correctly. Ain't got a clue what happened to Squirtle.