I'm sorry that you lose all your tribes but now you may have a New Start!!

I think that you must save regularly some Backups of your game so you may find again your tribes as you want. It's in Forums List » Windows/Mac Games (and Palm/Pocket PC) » Virtual Villagers 2: The Lost Children » Backing up and recovering savegame files

And also if you want some spoiler, you may go in Forums List » The Guides » Virtual Villagers 2: The Lost Children Guide there are a lot of spoiler and especially: General Strategy Guide; Hints for the 16 Puzzles; [BIG SPOILERS] Detailed solutions for the puzzles! by LadyCFII

Good luck to you and your new tribes!!